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Change the following Go code into Java without altering its purpose.
package main import "fmt" func main() { tableA := []struct { value int key string }{ {27, "Jonah"}, {18, "Alan"}, {28, "Glory"}, {18, "Popeye"}, {28, "Alan"}, } tableB := []struct { key string value string }{ {"Jonah", "Whales"}, {"Jonah", "Spiders"}, {"Alan", "Ghosts"}, {"Alan", "Zombies"}, {"Glory", "Buffy"}, } h := map[string][]int{} for i, r := range tableA { h[r.key] = append(h[r.key], i) } for _, x := range tableB { for _, a := range h[x.key] { fmt.Println(tableA[a], x) } } }
import java.util.*; public class HashJoin { public static void main(String[] args) { String[][] table1 = {{"27", "Jonah"}, {"18", "Alan"}, {"28", "Glory"}, {"18", "Popeye"}, {"28", "Alan"}}; String[][] table2 = {{"Jonah", "Whales"}, {"Jonah", "Spiders"}, {"Alan", "Ghosts"}, {"Alan", "Zombies"}, {"Glory", "Buffy"}, {"Bob", "foo"}}; hashJoin(table1, 1, table2, 0).stream() .forEach(r -> System.out.println(Arrays.deepToString(r))); } static List<String[][]> hashJoin(String[][] records1, int idx1, String[][] records2, int idx2) { List<String[][]> result = new ArrayList<>(); Map<String, List<String[]>> map = new HashMap<>(); for (String[] record : records1) { List<String[]> v = map.getOrDefault(record[idx1], new ArrayList<>()); v.add(record); map.put(record[idx1], v); } for (String[] record : records2) { List<String[]> lst = map.get(record[idx2]); if (lst != null) { lst.stream().forEach(r -> { result.add(new String[][]{r, record}); }); } } return result; } }
Translate the given Go code snippet into Java without altering its behavior.
package main import ( "fmt" "math" "rcu" "time" ) var count []int func primeCounter(limit int) { count = make([]int, limit) for i := 0; i < limit; i++ { count[i] = 1 } if limit > 0 { count[0] = 0 } if limit > 1 { count[1] = 0 } for i := 4; i < limit; i += 2 { count[i] = 0 } for p, sq := 3, 9; sq < limit; p += 2 { if count[p] != 0 { for q := sq; q < limit; q += p << 1 { count[q] = 0 } } sq += (p + 1) << 2 } sum := 0 for i := 0; i < limit; i++ { sum += count[i] count[i] = sum } } func primeCount(n int) int { if n < 1 { return 0 } return count[n] } func ramanujanMax(n int) int { fn := float64(n) return int(math.Ceil(4 * fn * math.Log(4*fn))) } func ramanujanPrime(n int) int { if n == 1 { return 2 } for i := ramanujanMax(n); i >= 2*n; i-- { if i%2 == 1 { continue } if primeCount(i)-primeCount(i/2) < n { return i + 1 } } return 0 } func main() { start := time.Now() primeCounter(1 + ramanujanMax(1e6)) fmt.Println("The first 100 Ramanujan primes are:") rams := make([]int, 100) for n := 0; n < 100; n++ { rams[n] = ramanujanPrime(n + 1) } for i, r := range rams { fmt.Printf("%5s ", rcu.Commatize(r)) if (i+1)%10 == 0 { fmt.Println() } } fmt.Printf("\nThe 1,000th Ramanujan prime is %6s\n", rcu.Commatize(ramanujanPrime(1000))) fmt.Printf("\nThe 10,000th Ramanujan prime is %7s\n", rcu.Commatize(ramanujanPrime(10000))) fmt.Printf("\nThe 100,000th Ramanujan prime is %6s\n", rcu.Commatize(ramanujanPrime(100000))) fmt.Printf("\nThe 1,000,000th Ramanujan prime is %7s\n", rcu.Commatize(ramanujanPrime(1000000))) fmt.Println("\nTook", time.Since(start)) }
import java.util.Arrays; public class RamanujanPrimes { public static void main(String[] args) { long start = System.nanoTime(); System.out.println("First 100 Ramanujan primes:"); PrimeCounter pc = new PrimeCounter(1 + ramanujanMax(100000)); for (int i = 1; i <= 100; ++i) { int p = ramanujanPrime(pc, i); System.out.printf("%,5d%c", p, i % 10 == 0 ? '\n' : ' '); } System.out.println(); for (int i = 1000; i <= 100000; i *= 10) { int p = ramanujanPrime(pc, i); System.out.printf("The %,dth Ramanujan prime is %,d.\n", i, p); } long end = System.nanoTime(); System.out.printf("\nElapsed time: %.1f milliseconds\n", (end - start) / 1e6); } private static int ramanujanMax(int n) { return (int)Math.ceil(4 * n * Math.log(4 * n)); } private static int ramanujanPrime(PrimeCounter pc, int n) { for (int i = ramanujanMax(n); i >= 0; --i) { if (pc.primeCount(i) - pc.primeCount(i / 2) < n) return i + 1; } return 0; } private static class PrimeCounter { private PrimeCounter(int limit) { count = new int[limit]; Arrays.fill(count, 1); if (limit > 0) count[0] = 0; if (limit > 1) count[1] = 0; for (int i = 4; i < limit; i += 2) count[i] = 0; for (int p = 3, sq = 9; sq < limit; p += 2) { if (count[p] != 0) { for (int q = sq; q < limit; q += p << 1) count[q] = 0; } sq += (p + 1) << 2; } Arrays.parallelPrefix(count, (x, y) -> x + y); } private int primeCount(int n) { return n < 1 ? 0 : count[n]; } private int[] count; } }
Maintain the same structure and functionality when rewriting this code in Java.
package main import ( "fmt" "math" "rcu" "time" ) var count []int func primeCounter(limit int) { count = make([]int, limit) for i := 0; i < limit; i++ { count[i] = 1 } if limit > 0 { count[0] = 0 } if limit > 1 { count[1] = 0 } for i := 4; i < limit; i += 2 { count[i] = 0 } for p, sq := 3, 9; sq < limit; p += 2 { if count[p] != 0 { for q := sq; q < limit; q += p << 1 { count[q] = 0 } } sq += (p + 1) << 2 } sum := 0 for i := 0; i < limit; i++ { sum += count[i] count[i] = sum } } func primeCount(n int) int { if n < 1 { return 0 } return count[n] } func ramanujanMax(n int) int { fn := float64(n) return int(math.Ceil(4 * fn * math.Log(4*fn))) } func ramanujanPrime(n int) int { if n == 1 { return 2 } for i := ramanujanMax(n); i >= 2*n; i-- { if i%2 == 1 { continue } if primeCount(i)-primeCount(i/2) < n { return i + 1 } } return 0 } func main() { start := time.Now() primeCounter(1 + ramanujanMax(1e6)) fmt.Println("The first 100 Ramanujan primes are:") rams := make([]int, 100) for n := 0; n < 100; n++ { rams[n] = ramanujanPrime(n + 1) } for i, r := range rams { fmt.Printf("%5s ", rcu.Commatize(r)) if (i+1)%10 == 0 { fmt.Println() } } fmt.Printf("\nThe 1,000th Ramanujan prime is %6s\n", rcu.Commatize(ramanujanPrime(1000))) fmt.Printf("\nThe 10,000th Ramanujan prime is %7s\n", rcu.Commatize(ramanujanPrime(10000))) fmt.Printf("\nThe 100,000th Ramanujan prime is %6s\n", rcu.Commatize(ramanujanPrime(100000))) fmt.Printf("\nThe 1,000,000th Ramanujan prime is %7s\n", rcu.Commatize(ramanujanPrime(1000000))) fmt.Println("\nTook", time.Since(start)) }
import java.util.Arrays; public class RamanujanPrimes { public static void main(String[] args) { long start = System.nanoTime(); System.out.println("First 100 Ramanujan primes:"); PrimeCounter pc = new PrimeCounter(1 + ramanujanMax(100000)); for (int i = 1; i <= 100; ++i) { int p = ramanujanPrime(pc, i); System.out.printf("%,5d%c", p, i % 10 == 0 ? '\n' : ' '); } System.out.println(); for (int i = 1000; i <= 100000; i *= 10) { int p = ramanujanPrime(pc, i); System.out.printf("The %,dth Ramanujan prime is %,d.\n", i, p); } long end = System.nanoTime(); System.out.printf("\nElapsed time: %.1f milliseconds\n", (end - start) / 1e6); } private static int ramanujanMax(int n) { return (int)Math.ceil(4 * n * Math.log(4 * n)); } private static int ramanujanPrime(PrimeCounter pc, int n) { for (int i = ramanujanMax(n); i >= 0; --i) { if (pc.primeCount(i) - pc.primeCount(i / 2) < n) return i + 1; } return 0; } private static class PrimeCounter { private PrimeCounter(int limit) { count = new int[limit]; Arrays.fill(count, 1); if (limit > 0) count[0] = 0; if (limit > 1) count[1] = 0; for (int i = 4; i < limit; i += 2) count[i] = 0; for (int p = 3, sq = 9; sq < limit; p += 2) { if (count[p] != 0) { for (int q = sq; q < limit; q += p << 1) count[q] = 0; } sq += (p + 1) << 2; } Arrays.parallelPrefix(count, (x, y) -> x + y); } private int primeCount(int n) { return n < 1 ? 0 : count[n]; } private int[] count; } }
Preserve the algorithm and functionality while converting the code from Go to Java.
package main import ( "github.com/fogleman/gg" "math" ) var ( width = 770.0 height = 770.0 dc = gg.NewContext(int(width), int(height)) ) var cx, cy, h float64 func lineTo(newX, newY float64) { dc.LineTo(newX-width/2+h, height-newY+2*h) cx, cy = newX, newY } func lineN() { lineTo(cx, cy-2*h) } func lineS() { lineTo(cx, cy+2*h) } func lineE() { lineTo(cx+2*h, cy) } func lineW() { lineTo(cx-2*h, cy) } func lineNW() { lineTo(cx-h, cy-h) } func lineNE() { lineTo(cx+h, cy-h) } func lineSE() { lineTo(cx+h, cy+h) } func lineSW() { lineTo(cx-h, cy+h) } func sierN(level int) { if level == 1 { lineNE() lineN() lineNW() } else { sierN(level - 1) lineNE() sierE(level - 1) lineN() sierW(level - 1) lineNW() sierN(level - 1) } } func sierE(level int) { if level == 1 { lineSE() lineE() lineNE() } else { sierE(level - 1) lineSE() sierS(level - 1) lineE() sierN(level - 1) lineNE() sierE(level - 1) } } func sierS(level int) { if level == 1 { lineSW() lineS() lineSE() } else { sierS(level - 1) lineSW() sierW(level - 1) lineS() sierE(level - 1) lineSE() sierS(level - 1) } } func sierW(level int) { if level == 1 { lineNW() lineW() lineSW() } else { sierW(level - 1) lineNW() sierN(level - 1) lineW() sierS(level - 1) lineSW() sierW(level - 1) } } func squareCurve(level int) { sierN(level) lineNE() sierE(level) lineSE() sierS(level) lineSW() sierW(level) lineNW() lineNE() } func main() { dc.SetRGB(0, 0, 1) dc.Clear() level := 5 cx, cy = width/2, height h = cx / math.Pow(2, float64(level+1)) squareCurve(level) dc.SetRGB255(255, 255, 0) dc.SetLineWidth(2) dc.Stroke() dc.SavePNG("sierpinski_curve.png") }
import java.io.*; public class SierpinskiCurve { public static void main(final String[] args) { try (Writer writer = new BufferedWriter(new FileWriter("sierpinski_curve.svg"))) { SierpinskiCurve s = new SierpinskiCurve(writer); s.currentAngle = 45; s.currentX = 5; s.currentY = 10; s.lineLength = 7; s.begin(545); s.execute(rewrite(5)); s.end(); } catch (final Exception ex) { ex.printStackTrace(); } } private SierpinskiCurve(final Writer writer) { this.writer = writer; } private void begin(final int size) throws IOException { write("<svg xmlns='http: write("<rect width='100%%' height='100%%' fill='white'/>\n"); write("<path stroke-width='1' stroke='black' fill='none' d='"); } private void end() throws IOException { write("'/>\n</svg>\n"); } private void execute(final String s) throws IOException { write("M%g,%g\n", currentX, currentY); for (int i = 0, n = s.length(); i < n; ++i) { switch (s.charAt(i)) { case 'F': case 'G': line(lineLength); break; case '+': turn(ANGLE); break; case '-': turn(-ANGLE); break; } } } private void line(final double length) throws IOException { final double theta = (Math.PI * currentAngle) / 180.0; currentX += length * Math.cos(theta); currentY -= length * Math.sin(theta); write("L%g,%g\n", currentX, currentY); } private void turn(final int angle) { currentAngle = (currentAngle + angle) % 360; } private void write(final String format, final Object... args) throws IOException { writer.write(String.format(format, args)); } private static String rewrite(final int order) { String s = AXIOM; for (int i = 0; i < order; ++i) { final StringBuilder sb = new StringBuilder(); for (int j = 0, n = s.length(); j < n; ++j) { final char ch = s.charAt(j); if (ch == 'X') sb.append(PRODUCTION); else sb.append(ch); } s = sb.toString(); } return s; } private final Writer writer; private double lineLength; private double currentX; private double currentY; private int currentAngle; private static final String AXIOM = "F--XF--F--XF"; private static final String PRODUCTION = "XF+G+XF--F--XF+G+X"; private static final int ANGLE = 45; }
Can you help me rewrite this code in Java instead of Go, keeping it the same logically?
package main import ( "github.com/fogleman/gg" "math" ) var ( width = 770.0 height = 770.0 dc = gg.NewContext(int(width), int(height)) ) var cx, cy, h float64 func lineTo(newX, newY float64) { dc.LineTo(newX-width/2+h, height-newY+2*h) cx, cy = newX, newY } func lineN() { lineTo(cx, cy-2*h) } func lineS() { lineTo(cx, cy+2*h) } func lineE() { lineTo(cx+2*h, cy) } func lineW() { lineTo(cx-2*h, cy) } func lineNW() { lineTo(cx-h, cy-h) } func lineNE() { lineTo(cx+h, cy-h) } func lineSE() { lineTo(cx+h, cy+h) } func lineSW() { lineTo(cx-h, cy+h) } func sierN(level int) { if level == 1 { lineNE() lineN() lineNW() } else { sierN(level - 1) lineNE() sierE(level - 1) lineN() sierW(level - 1) lineNW() sierN(level - 1) } } func sierE(level int) { if level == 1 { lineSE() lineE() lineNE() } else { sierE(level - 1) lineSE() sierS(level - 1) lineE() sierN(level - 1) lineNE() sierE(level - 1) } } func sierS(level int) { if level == 1 { lineSW() lineS() lineSE() } else { sierS(level - 1) lineSW() sierW(level - 1) lineS() sierE(level - 1) lineSE() sierS(level - 1) } } func sierW(level int) { if level == 1 { lineNW() lineW() lineSW() } else { sierW(level - 1) lineNW() sierN(level - 1) lineW() sierS(level - 1) lineSW() sierW(level - 1) } } func squareCurve(level int) { sierN(level) lineNE() sierE(level) lineSE() sierS(level) lineSW() sierW(level) lineNW() lineNE() } func main() { dc.SetRGB(0, 0, 1) dc.Clear() level := 5 cx, cy = width/2, height h = cx / math.Pow(2, float64(level+1)) squareCurve(level) dc.SetRGB255(255, 255, 0) dc.SetLineWidth(2) dc.Stroke() dc.SavePNG("sierpinski_curve.png") }
import java.io.*; public class SierpinskiCurve { public static void main(final String[] args) { try (Writer writer = new BufferedWriter(new FileWriter("sierpinski_curve.svg"))) { SierpinskiCurve s = new SierpinskiCurve(writer); s.currentAngle = 45; s.currentX = 5; s.currentY = 10; s.lineLength = 7; s.begin(545); s.execute(rewrite(5)); s.end(); } catch (final Exception ex) { ex.printStackTrace(); } } private SierpinskiCurve(final Writer writer) { this.writer = writer; } private void begin(final int size) throws IOException { write("<svg xmlns='http: write("<rect width='100%%' height='100%%' fill='white'/>\n"); write("<path stroke-width='1' stroke='black' fill='none' d='"); } private void end() throws IOException { write("'/>\n</svg>\n"); } private void execute(final String s) throws IOException { write("M%g,%g\n", currentX, currentY); for (int i = 0, n = s.length(); i < n; ++i) { switch (s.charAt(i)) { case 'F': case 'G': line(lineLength); break; case '+': turn(ANGLE); break; case '-': turn(-ANGLE); break; } } } private void line(final double length) throws IOException { final double theta = (Math.PI * currentAngle) / 180.0; currentX += length * Math.cos(theta); currentY -= length * Math.sin(theta); write("L%g,%g\n", currentX, currentY); } private void turn(final int angle) { currentAngle = (currentAngle + angle) % 360; } private void write(final String format, final Object... args) throws IOException { writer.write(String.format(format, args)); } private static String rewrite(final int order) { String s = AXIOM; for (int i = 0; i < order; ++i) { final StringBuilder sb = new StringBuilder(); for (int j = 0, n = s.length(); j < n; ++j) { final char ch = s.charAt(j); if (ch == 'X') sb.append(PRODUCTION); else sb.append(ch); } s = sb.toString(); } return s; } private final Writer writer; private double lineLength; private double currentX; private double currentY; private int currentAngle; private static final String AXIOM = "F--XF--F--XF"; private static final String PRODUCTION = "XF+G+XF--F--XF+G+X"; private static final int ANGLE = 45; }
Convert the following code from Go to Java, ensuring the logic remains intact.
package main import ( "github.com/fogleman/gg" "math" ) var ( width = 770.0 height = 770.0 dc = gg.NewContext(int(width), int(height)) ) var cx, cy, h float64 func lineTo(newX, newY float64) { dc.LineTo(newX-width/2+h, height-newY+2*h) cx, cy = newX, newY } func lineN() { lineTo(cx, cy-2*h) } func lineS() { lineTo(cx, cy+2*h) } func lineE() { lineTo(cx+2*h, cy) } func lineW() { lineTo(cx-2*h, cy) } func lineNW() { lineTo(cx-h, cy-h) } func lineNE() { lineTo(cx+h, cy-h) } func lineSE() { lineTo(cx+h, cy+h) } func lineSW() { lineTo(cx-h, cy+h) } func sierN(level int) { if level == 1 { lineNE() lineN() lineNW() } else { sierN(level - 1) lineNE() sierE(level - 1) lineN() sierW(level - 1) lineNW() sierN(level - 1) } } func sierE(level int) { if level == 1 { lineSE() lineE() lineNE() } else { sierE(level - 1) lineSE() sierS(level - 1) lineE() sierN(level - 1) lineNE() sierE(level - 1) } } func sierS(level int) { if level == 1 { lineSW() lineS() lineSE() } else { sierS(level - 1) lineSW() sierW(level - 1) lineS() sierE(level - 1) lineSE() sierS(level - 1) } } func sierW(level int) { if level == 1 { lineNW() lineW() lineSW() } else { sierW(level - 1) lineNW() sierN(level - 1) lineW() sierS(level - 1) lineSW() sierW(level - 1) } } func squareCurve(level int) { sierN(level) lineNE() sierE(level) lineSE() sierS(level) lineSW() sierW(level) lineNW() lineNE() } func main() { dc.SetRGB(0, 0, 1) dc.Clear() level := 5 cx, cy = width/2, height h = cx / math.Pow(2, float64(level+1)) squareCurve(level) dc.SetRGB255(255, 255, 0) dc.SetLineWidth(2) dc.Stroke() dc.SavePNG("sierpinski_curve.png") }
import java.io.*; public class SierpinskiCurve { public static void main(final String[] args) { try (Writer writer = new BufferedWriter(new FileWriter("sierpinski_curve.svg"))) { SierpinskiCurve s = new SierpinskiCurve(writer); s.currentAngle = 45; s.currentX = 5; s.currentY = 10; s.lineLength = 7; s.begin(545); s.execute(rewrite(5)); s.end(); } catch (final Exception ex) { ex.printStackTrace(); } } private SierpinskiCurve(final Writer writer) { this.writer = writer; } private void begin(final int size) throws IOException { write("<svg xmlns='http: write("<rect width='100%%' height='100%%' fill='white'/>\n"); write("<path stroke-width='1' stroke='black' fill='none' d='"); } private void end() throws IOException { write("'/>\n</svg>\n"); } private void execute(final String s) throws IOException { write("M%g,%g\n", currentX, currentY); for (int i = 0, n = s.length(); i < n; ++i) { switch (s.charAt(i)) { case 'F': case 'G': line(lineLength); break; case '+': turn(ANGLE); break; case '-': turn(-ANGLE); break; } } } private void line(final double length) throws IOException { final double theta = (Math.PI * currentAngle) / 180.0; currentX += length * Math.cos(theta); currentY -= length * Math.sin(theta); write("L%g,%g\n", currentX, currentY); } private void turn(final int angle) { currentAngle = (currentAngle + angle) % 360; } private void write(final String format, final Object... args) throws IOException { writer.write(String.format(format, args)); } private static String rewrite(final int order) { String s = AXIOM; for (int i = 0; i < order; ++i) { final StringBuilder sb = new StringBuilder(); for (int j = 0, n = s.length(); j < n; ++j) { final char ch = s.charAt(j); if (ch == 'X') sb.append(PRODUCTION); else sb.append(ch); } s = sb.toString(); } return s; } private final Writer writer; private double lineLength; private double currentX; private double currentY; private int currentAngle; private static final String AXIOM = "F--XF--F--XF"; private static final String PRODUCTION = "XF+G+XF--F--XF+G+X"; private static final int ANGLE = 45; }
Convert this Go block to Java, preserving its control flow and logic.
package main import ( "fmt" "sort" ) type cf struct { c rune f int } func reverseStr(s string) string { runes := []rune(s) for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 { runes[i], runes[j] = runes[j], runes[i] } return string(runes) } func indexOfCf(cfs []cf, r rune) int { for i, cf := range cfs { if cf.c == r { return i } } return -1 } func minOf(i, j int) int { if i < j { return i } return j } func mostFreqKHashing(input string, k int) string { var cfs []cf for _, r := range input { ix := indexOfCf(cfs, r) if ix >= 0 { cfs[ix].f++ } else { cfs = append(cfs, cf{r, 1}) } } sort.SliceStable(cfs, func(i, j int) bool { return cfs[i].f > cfs[j].f }) acc := "" min := minOf(len(cfs), k) for _, cf := range cfs[:min] { acc += fmt.Sprintf("%c%c", cf.c, cf.f) } return acc } func mostFreqKSimilarity(input1, input2 string) int { similarity := 0 runes1, runes2 := []rune(input1), []rune(input2) for i := 0; i < len(runes1); i += 2 { for j := 0; j < len(runes2); j += 2 { if runes1[i] == runes2[j] { freq1, freq2 := runes1[i+1], runes2[j+1] if freq1 != freq2 { continue } similarity += int(freq1) } } } return similarity } func mostFreqKSDF(input1, input2 string, k, maxDistance int) { fmt.Println("input1 :", input1) fmt.Println("input2 :", input2) s1 := mostFreqKHashing(input1, k) s2 := mostFreqKHashing(input2, k) fmt.Printf("mfkh(input1, %d) = ", k) for i, c := range s1 { if i%2 == 0 { fmt.Printf("%c", c) } else { fmt.Printf("%d", c) } } fmt.Printf("\nmfkh(input2, %d) = ", k) for i, c := range s2 { if i%2 == 0 { fmt.Printf("%c", c) } else { fmt.Printf("%d", c) } } result := maxDistance - mostFreqKSimilarity(s1, s2) fmt.Printf("\nSDF(input1, input2, %d, %d) = %d\n\n", k, maxDistance, result) } func main() { pairs := [][2]string{ {"research", "seeking"}, {"night", "nacht"}, {"my", "a"}, {"research", "research"}, {"aaaaabbbb", "ababababa"}, {"significant", "capabilities"}, } for _, pair := range pairs { mostFreqKSDF(pair[0], pair[1], 2, 10) } s1 := "LCLYTHIGRNIYYGSYLYSETWNTGIMLLLITMATAFMGYVLPWGQMSFWGATVITNLFSAIPYIGTNLV" s2 := "EWIWGGFSVDKATLNRFFAFHFILPFTMVALAGVHLTFLHETGSNNPLGLTSDSDKIPFHPYYTIKDFLG" mostFreqKSDF(s1, s2, 2, 100) s1 = "abracadabra12121212121abracadabra12121212121" s2 = reverseStr(s1) mostFreqKSDF(s1, s2, 2, 100) }
import java.util.Collections; import java.util.Comparator; import java.util.HashMap; import java.util.LinkedHashMap; import java.util.ArrayList; import java.util.List; import java.util.Map; public class SDF { public static HashMap<Character, Integer> countElementOcurrences(char[] array) { HashMap<Character, Integer> countMap = new HashMap<Character, Integer>(); for (char element : array) { Integer count = countMap.get(element); count = (count == null) ? 1 : count + 1; countMap.put(element, count); } return countMap; } private static <K, V extends Comparable<? super V>> HashMap<K, V> descendingSortByValues(HashMap<K, V> map) { List<Map.Entry<K, V>> list = new ArrayList<Map.Entry<K, V>>(map.entrySet()); Collections.sort(list, new Comparator<Map.Entry<K, V>>() { public int compare(Map.Entry<K, V> o1, Map.Entry<K, V> o2) { return o2.getValue().compareTo(o1.getValue()); } }); HashMap<K, V> sortedHashMap = new LinkedHashMap<K, V>(); for (Map.Entry<K, V> entry : list) { sortedHashMap.put(entry.getKey(), entry.getValue()); } return sortedHashMap; } public static String mostOcurrencesElement(char[] array, int k) { HashMap<Character, Integer> countMap = countElementOcurrences(array); System.out.println(countMap); Map<Character, Integer> map = descendingSortByValues(countMap); System.out.println(map); int i = 0; String output = ""; for (Map.Entry<Character, Integer> pairs : map.entrySet()) { if (i++ >= k) break; output += "" + pairs.getKey() + pairs.getValue(); } return output; } public static int getDiff(String str1, String str2, int limit) { int similarity = 0; int k = 0; for (int i = 0; i < str1.length() ; i = k) { k ++; if (Character.isLetter(str1.charAt(i))) { int pos = str2.indexOf(str1.charAt(i)); if (pos >= 0) { String digitStr1 = ""; while ( k < str1.length() && !Character.isLetter(str1.charAt(k))) { digitStr1 += str1.charAt(k); k++; } int k2 = pos+1; String digitStr2 = ""; while (k2 < str2.length() && !Character.isLetter(str2.charAt(k2)) ) { digitStr2 += str2.charAt(k2); k2++; } similarity += Integer.parseInt(digitStr2) + Integer.parseInt(digitStr1); } } } return Math.abs(limit - similarity); } public static int SDFfunc(String str1, String str2, int limit) { return getDiff(mostOcurrencesElement(str1.toCharArray(), 2), mostOcurrencesElement(str2.toCharArray(), 2), limit); } public static void main(String[] args) { String input1 = "LCLYTHIGRNIYYGSYLYSETWNTGIMLLLITMATAFMGYVLPWGQMSFWGATVITNLFSAIPYIGTNLV"; String input2 = "EWIWGGFSVDKATLNRFFAFHFILPFTMVALAGVHLTFLHETGSNNPLGLTSDSDKIPFHPYYTIKDFLG"; System.out.println(SDF.SDFfunc(input1,input2,100)); } }
Can you help me rewrite this code in Java instead of Go, keeping it the same logically?
package main import ( "bytes" "fmt" "io/ioutil" "log" ) func levenshtein(s, t string) int { d := make([][]int, len(s)+1) for i := range d { d[i] = make([]int, len(t)+1) } for i := range d { d[i][0] = i } for j := range d[0] { d[0][j] = j } for j := 1; j <= len(t); j++ { for i := 1; i <= len(s); i++ { if s[i-1] == t[j-1] { d[i][j] = d[i-1][j-1] } else { min := d[i-1][j] if d[i][j-1] < min { min = d[i][j-1] } if d[i-1][j-1] < min { min = d[i-1][j-1] } d[i][j] = min + 1 } } } return d[len(s)][len(t)] } func main() { search := "complition" b, err := ioutil.ReadFile("unixdict.txt") if err != nil { log.Fatal("Error reading file") } words := bytes.Fields(b) var lev [4][]string for _, word := range words { s := string(word) ld := levenshtein(search, s) if ld < 4 { lev[ld] = append(lev[ld], s) } } fmt.Printf("Input word: %s\n\n", search) for i := 1; i < 4; i++ { length := float64(len(search)) similarity := (length - float64(i)) * 100 / length fmt.Printf("Words which are %4.1f%% similar:\n", similarity) fmt.Println(lev[i]) fmt.Println() } }
import java.io.File; import java.io.IOException; import java.net.URISyntaxException; import java.util.ArrayList; import java.util.Scanner; public class textCompletionConcept { public static int correct = 0; public static ArrayList<String> listed = new ArrayList<>(); public static void main(String[]args) throws IOException, URISyntaxException { Scanner input = new Scanner(System.in); System.out.println("Input word: "); String errorRode = input.next(); File file = new File(new File(textCompletionConcept.class.getProtectionDomain().getCodeSource().getLocation().toURI()).getPath() + File.separator + "words.txt"); Scanner reader = new Scanner(file); while(reader.hasNext()){ double percent; String compareToThis = reader.nextLine(); char[] s1 = errorRode.toCharArray(); char[] s2 = compareToThis.toCharArray(); int maxlen = Math.min(s1.length, s2.length); for (int index = 0; index < maxlen; index++) { String x = String.valueOf(s1[index]); String y = String.valueOf(s2[index]); if (x.equals(y)) { correct++; } } double length = Math.max(s1.length, s2.length); percent = correct / length; percent *= 100; boolean perfect = false; if (percent >= 80 && compareToThis.charAt(0) == errorRode.charAt(0)) { if(String.valueOf(percent).equals("100.00")){ perfect = true; } String addtoit = compareToThis + " : " + String.format("%.2f", percent) + "% similar."; listed.add(addtoit); } if(compareToThis.contains(errorRode) && !perfect && errorRode.length() * 2 > compareToThis.length()){ String addtoit = compareToThis + " : 80.00% similar."; listed.add(addtoit); } correct = 0; } for(String x : listed){ if(x.contains("100.00% similar.")){ System.out.println(x); listed.clear(); break; } } for(String x : listed){ System.out.println(x); } } }
Change the following Go code into Java without altering its purpose.
package pig import ( "fmt" "math/rand" "time" ) type ( PlayerID int MessageID int StrategyID int PigGameData struct { player PlayerID turnCount int turnRollCount int turnScore int lastRoll int scores [2]int verbose bool } ) const ( gameOver = iota piggedOut rolls pointSpending holds turn gameOverSummary player1 = PlayerID(0) player2 = PlayerID(1) noPlayer = PlayerID(-1) maxScore = 100 scoreChaseStrat = iota rollCountStrat ) func pluralS(n int) string { if n != 1 { return "s" } return "" } func New() *PigGameData { return &PigGameData{0, 0, 0, 0, 0, [2]int{0, 0}, false} } func (pg *PigGameData) statusMessage(id MessageID) string { var msg string switch id { case gameOver: msg = fmt.Sprintf("Game is over after %d turns", pg.turnCount) case piggedOut: msg = fmt.Sprintf(" Pigged out after %d roll%s", pg.turnRollCount, pluralS(pg.turnRollCount)) case rolls: msg = fmt.Sprintf(" Rolls %d", pg.lastRoll) case pointSpending: msg = fmt.Sprintf(" %d point%s pending", pg.turnScore, pluralS(pg.turnScore)) case holds: msg = fmt.Sprintf(" Holds after %d turns, adding %d points for a total of %d", pg.turnRollCount, pg.turnScore, pg.PlayerScore(noPlayer)) case turn: msg = fmt.Sprintf("Player %d's turn:", pg.player+1) case gameOverSummary: msg = fmt.Sprintf("Game over after %d turns\n player 1 %d\n player 2 %d\n", pg.turnCount, pg.PlayerScore(player1), pg.PlayerScore(player2)) } return msg } func (pg *PigGameData) PrintStatus(id MessageID) { if pg.verbose { fmt.Println(pg.statusMessage(id)) } } func (pg *PigGameData) Play(id StrategyID) (keepPlaying bool) { if pg.GameOver() { pg.PrintStatus(gameOver) return false } if pg.turnCount == 0 { pg.player = player2 pg.NextPlayer() } pg.lastRoll = rand.Intn(6) + 1 pg.PrintStatus(rolls) pg.turnRollCount++ if pg.lastRoll == 1 { pg.PrintStatus(piggedOut) pg.NextPlayer() } else { pg.turnScore += pg.lastRoll pg.PrintStatus(pointSpending) success := false switch id { case scoreChaseStrat: success = pg.scoreChaseStrategy() case rollCountStrat: success = pg.rollCountStrategy() } if success { pg.Hold() pg.NextPlayer() } } return true } func (pg *PigGameData) PlayerScore(id PlayerID) int { if id == noPlayer { return pg.scores[pg.player] } return pg.scores[id] } func (pg *PigGameData) GameOver() bool { return pg.scores[player1] >= maxScore || pg.scores[player2] >= maxScore } func (pg *PigGameData) Winner() PlayerID { for index, score := range pg.scores { if score >= maxScore { return PlayerID(index) } } return noPlayer } func (pg *PigGameData) otherPlayer() PlayerID { return 1 - pg.player } func (pg *PigGameData) Hold() { pg.scores[pg.player] += pg.turnScore pg.PrintStatus(holds) pg.turnRollCount, pg.turnScore = 0, 0 } func (pg *PigGameData) NextPlayer() { pg.turnCount++ pg.turnRollCount, pg.turnScore = 0, 0 pg.player = pg.otherPlayer() pg.PrintStatus(turn) } func (pg *PigGameData) rollCountStrategy() bool { return pg.turnRollCount >= 3 } func (pg *PigGameData) scoreChaseStrategy() bool { myScore := pg.PlayerScore(pg.player) otherScore := pg.PlayerScore(pg.otherPlayer()) myPendingScore := pg.turnScore + myScore return myPendingScore >= maxScore || myPendingScore > otherScore || pg.turnRollCount >= 5 } func main() { rand.Seed(time.Now().UnixNano()) pg := New() pg.verbose = true strategies := [2]StrategyID{scoreChaseStrat, rollCountStrat} for !pg.GameOver() { pg.Play(strategies[pg.player]) } pg.PrintStatus(gameOverSummary) }
import java.util.Scanner; public class Pigdice { public static void main(String[] args) { Scanner scan = new Scanner(System.in); int players = 0; while(true) { System.out.println("Hello, welcome to Pig Dice the game! How many players? "); if(scan.hasNextInt()) { int nextInt = scan.nextInt(); if(nextInt > 0) { players = nextInt; break; } } else { System.out.println("That wasn't an integer. Try again. \n"); scan.next(); } } System.out.println("Alright, starting with " + players + " players. \n"); play(players, scan); scan.close(); } public static void play(int group, Scanner scan) { final int STRATEGIES = 5; Dice dice = new Dice(); Player[] players = new Player[group]; for(int count = 0; count < group; count++) { players[count] = new Player(count); System.out.println("Player " + players[count].getNumber() + " is alive! "); } System.out.println("Each strategy is numbered 0 - " + (STRATEGIES - 1) + ". They are as follows: "); System.out.println(">> Enter '0' for a human player. "); System.out.println(">> Strategy 1 is a basic strategy where the AI rolls until 20+ points and holds unless the current max is 75+."); System.out.println(">> Strategy 2 is a basic strategy where the AI, after 3 successful rolls, will randomly decide to roll or hold. "); System.out.println(">> Strategy 3 is similar to strategy 2, except it's a little gutsier and will attempt 5 successful rolls. "); System.out.println(">> Strategy 4 is like a mix between strategies 1 and 3. After turn points are >= 20 and while max points are still less than 75, it will randomly hold or roll. "); for(Player player : players) { System.out.println("\nWhat strategy would you like player " + player.getNumber() + " to use? "); while(true) { if(scan.hasNextInt()) { int nextInt = scan.nextInt(); if (nextInt < Strategy.STRATEGIES.length) { player.setStrategy(Strategy.STRATEGIES[nextInt]); break; } } else { System.out.println("That wasn't an option. Try again. "); scan.next(); } } } int max = 0; while(max < 100) { for(Player player : players) { System.out.println(">> Beginning Player " + player.getNumber() + "'s turn. "); player.setTurnPoints(0); player.setMax(max); while(true) { Move choice = player.choose(); if(choice == Move.ROLL) { int roll = dice.roll(); System.out.println(" A " + roll + " was rolled. "); player.setTurnPoints(player.getTurnPoints() + roll); player.incIter(); if(roll == 1) { player.setTurnPoints(0); break; } } else { System.out.println(" The player has held. "); break; } } player.addPoints(player.getTurnPoints()); System.out.println(" Player " + player.getNumber() + "'s turn is now over. Their total is " + player.getPoints() + ". \n"); player.resetIter(); if(max < player.getPoints()) { max = player.getPoints(); } if(max >= 100) { System.out.println("Player " + player.getNumber() + " wins with " + max + " points! End scores: "); for(Player p : players) { System.out.println("Player " + p.getNumber() + " had " + p.getPoints() + " points. "); } break; } } } } }
Generate a Java translation of this Go snippet without changing its computational steps.
package pig import ( "fmt" "math/rand" "time" ) type ( PlayerID int MessageID int StrategyID int PigGameData struct { player PlayerID turnCount int turnRollCount int turnScore int lastRoll int scores [2]int verbose bool } ) const ( gameOver = iota piggedOut rolls pointSpending holds turn gameOverSummary player1 = PlayerID(0) player2 = PlayerID(1) noPlayer = PlayerID(-1) maxScore = 100 scoreChaseStrat = iota rollCountStrat ) func pluralS(n int) string { if n != 1 { return "s" } return "" } func New() *PigGameData { return &PigGameData{0, 0, 0, 0, 0, [2]int{0, 0}, false} } func (pg *PigGameData) statusMessage(id MessageID) string { var msg string switch id { case gameOver: msg = fmt.Sprintf("Game is over after %d turns", pg.turnCount) case piggedOut: msg = fmt.Sprintf(" Pigged out after %d roll%s", pg.turnRollCount, pluralS(pg.turnRollCount)) case rolls: msg = fmt.Sprintf(" Rolls %d", pg.lastRoll) case pointSpending: msg = fmt.Sprintf(" %d point%s pending", pg.turnScore, pluralS(pg.turnScore)) case holds: msg = fmt.Sprintf(" Holds after %d turns, adding %d points for a total of %d", pg.turnRollCount, pg.turnScore, pg.PlayerScore(noPlayer)) case turn: msg = fmt.Sprintf("Player %d's turn:", pg.player+1) case gameOverSummary: msg = fmt.Sprintf("Game over after %d turns\n player 1 %d\n player 2 %d\n", pg.turnCount, pg.PlayerScore(player1), pg.PlayerScore(player2)) } return msg } func (pg *PigGameData) PrintStatus(id MessageID) { if pg.verbose { fmt.Println(pg.statusMessage(id)) } } func (pg *PigGameData) Play(id StrategyID) (keepPlaying bool) { if pg.GameOver() { pg.PrintStatus(gameOver) return false } if pg.turnCount == 0 { pg.player = player2 pg.NextPlayer() } pg.lastRoll = rand.Intn(6) + 1 pg.PrintStatus(rolls) pg.turnRollCount++ if pg.lastRoll == 1 { pg.PrintStatus(piggedOut) pg.NextPlayer() } else { pg.turnScore += pg.lastRoll pg.PrintStatus(pointSpending) success := false switch id { case scoreChaseStrat: success = pg.scoreChaseStrategy() case rollCountStrat: success = pg.rollCountStrategy() } if success { pg.Hold() pg.NextPlayer() } } return true } func (pg *PigGameData) PlayerScore(id PlayerID) int { if id == noPlayer { return pg.scores[pg.player] } return pg.scores[id] } func (pg *PigGameData) GameOver() bool { return pg.scores[player1] >= maxScore || pg.scores[player2] >= maxScore } func (pg *PigGameData) Winner() PlayerID { for index, score := range pg.scores { if score >= maxScore { return PlayerID(index) } } return noPlayer } func (pg *PigGameData) otherPlayer() PlayerID { return 1 - pg.player } func (pg *PigGameData) Hold() { pg.scores[pg.player] += pg.turnScore pg.PrintStatus(holds) pg.turnRollCount, pg.turnScore = 0, 0 } func (pg *PigGameData) NextPlayer() { pg.turnCount++ pg.turnRollCount, pg.turnScore = 0, 0 pg.player = pg.otherPlayer() pg.PrintStatus(turn) } func (pg *PigGameData) rollCountStrategy() bool { return pg.turnRollCount >= 3 } func (pg *PigGameData) scoreChaseStrategy() bool { myScore := pg.PlayerScore(pg.player) otherScore := pg.PlayerScore(pg.otherPlayer()) myPendingScore := pg.turnScore + myScore return myPendingScore >= maxScore || myPendingScore > otherScore || pg.turnRollCount >= 5 } func main() { rand.Seed(time.Now().UnixNano()) pg := New() pg.verbose = true strategies := [2]StrategyID{scoreChaseStrat, rollCountStrat} for !pg.GameOver() { pg.Play(strategies[pg.player]) } pg.PrintStatus(gameOverSummary) }
import java.util.Scanner; public class Pigdice { public static void main(String[] args) { Scanner scan = new Scanner(System.in); int players = 0; while(true) { System.out.println("Hello, welcome to Pig Dice the game! How many players? "); if(scan.hasNextInt()) { int nextInt = scan.nextInt(); if(nextInt > 0) { players = nextInt; break; } } else { System.out.println("That wasn't an integer. Try again. \n"); scan.next(); } } System.out.println("Alright, starting with " + players + " players. \n"); play(players, scan); scan.close(); } public static void play(int group, Scanner scan) { final int STRATEGIES = 5; Dice dice = new Dice(); Player[] players = new Player[group]; for(int count = 0; count < group; count++) { players[count] = new Player(count); System.out.println("Player " + players[count].getNumber() + " is alive! "); } System.out.println("Each strategy is numbered 0 - " + (STRATEGIES - 1) + ". They are as follows: "); System.out.println(">> Enter '0' for a human player. "); System.out.println(">> Strategy 1 is a basic strategy where the AI rolls until 20+ points and holds unless the current max is 75+."); System.out.println(">> Strategy 2 is a basic strategy where the AI, after 3 successful rolls, will randomly decide to roll or hold. "); System.out.println(">> Strategy 3 is similar to strategy 2, except it's a little gutsier and will attempt 5 successful rolls. "); System.out.println(">> Strategy 4 is like a mix between strategies 1 and 3. After turn points are >= 20 and while max points are still less than 75, it will randomly hold or roll. "); for(Player player : players) { System.out.println("\nWhat strategy would you like player " + player.getNumber() + " to use? "); while(true) { if(scan.hasNextInt()) { int nextInt = scan.nextInt(); if (nextInt < Strategy.STRATEGIES.length) { player.setStrategy(Strategy.STRATEGIES[nextInt]); break; } } else { System.out.println("That wasn't an option. Try again. "); scan.next(); } } } int max = 0; while(max < 100) { for(Player player : players) { System.out.println(">> Beginning Player " + player.getNumber() + "'s turn. "); player.setTurnPoints(0); player.setMax(max); while(true) { Move choice = player.choose(); if(choice == Move.ROLL) { int roll = dice.roll(); System.out.println(" A " + roll + " was rolled. "); player.setTurnPoints(player.getTurnPoints() + roll); player.incIter(); if(roll == 1) { player.setTurnPoints(0); break; } } else { System.out.println(" The player has held. "); break; } } player.addPoints(player.getTurnPoints()); System.out.println(" Player " + player.getNumber() + "'s turn is now over. Their total is " + player.getPoints() + ". \n"); player.resetIter(); if(max < player.getPoints()) { max = player.getPoints(); } if(max >= 100) { System.out.println("Player " + player.getNumber() + " wins with " + max + " points! End scores: "); for(Player p : players) { System.out.println("Player " + p.getNumber() + " had " + p.getPoints() + " points. "); } break; } } } } }
Change the following Go code into Java without altering its purpose.
package pig import ( "fmt" "math/rand" "time" ) type ( PlayerID int MessageID int StrategyID int PigGameData struct { player PlayerID turnCount int turnRollCount int turnScore int lastRoll int scores [2]int verbose bool } ) const ( gameOver = iota piggedOut rolls pointSpending holds turn gameOverSummary player1 = PlayerID(0) player2 = PlayerID(1) noPlayer = PlayerID(-1) maxScore = 100 scoreChaseStrat = iota rollCountStrat ) func pluralS(n int) string { if n != 1 { return "s" } return "" } func New() *PigGameData { return &PigGameData{0, 0, 0, 0, 0, [2]int{0, 0}, false} } func (pg *PigGameData) statusMessage(id MessageID) string { var msg string switch id { case gameOver: msg = fmt.Sprintf("Game is over after %d turns", pg.turnCount) case piggedOut: msg = fmt.Sprintf(" Pigged out after %d roll%s", pg.turnRollCount, pluralS(pg.turnRollCount)) case rolls: msg = fmt.Sprintf(" Rolls %d", pg.lastRoll) case pointSpending: msg = fmt.Sprintf(" %d point%s pending", pg.turnScore, pluralS(pg.turnScore)) case holds: msg = fmt.Sprintf(" Holds after %d turns, adding %d points for a total of %d", pg.turnRollCount, pg.turnScore, pg.PlayerScore(noPlayer)) case turn: msg = fmt.Sprintf("Player %d's turn:", pg.player+1) case gameOverSummary: msg = fmt.Sprintf("Game over after %d turns\n player 1 %d\n player 2 %d\n", pg.turnCount, pg.PlayerScore(player1), pg.PlayerScore(player2)) } return msg } func (pg *PigGameData) PrintStatus(id MessageID) { if pg.verbose { fmt.Println(pg.statusMessage(id)) } } func (pg *PigGameData) Play(id StrategyID) (keepPlaying bool) { if pg.GameOver() { pg.PrintStatus(gameOver) return false } if pg.turnCount == 0 { pg.player = player2 pg.NextPlayer() } pg.lastRoll = rand.Intn(6) + 1 pg.PrintStatus(rolls) pg.turnRollCount++ if pg.lastRoll == 1 { pg.PrintStatus(piggedOut) pg.NextPlayer() } else { pg.turnScore += pg.lastRoll pg.PrintStatus(pointSpending) success := false switch id { case scoreChaseStrat: success = pg.scoreChaseStrategy() case rollCountStrat: success = pg.rollCountStrategy() } if success { pg.Hold() pg.NextPlayer() } } return true } func (pg *PigGameData) PlayerScore(id PlayerID) int { if id == noPlayer { return pg.scores[pg.player] } return pg.scores[id] } func (pg *PigGameData) GameOver() bool { return pg.scores[player1] >= maxScore || pg.scores[player2] >= maxScore } func (pg *PigGameData) Winner() PlayerID { for index, score := range pg.scores { if score >= maxScore { return PlayerID(index) } } return noPlayer } func (pg *PigGameData) otherPlayer() PlayerID { return 1 - pg.player } func (pg *PigGameData) Hold() { pg.scores[pg.player] += pg.turnScore pg.PrintStatus(holds) pg.turnRollCount, pg.turnScore = 0, 0 } func (pg *PigGameData) NextPlayer() { pg.turnCount++ pg.turnRollCount, pg.turnScore = 0, 0 pg.player = pg.otherPlayer() pg.PrintStatus(turn) } func (pg *PigGameData) rollCountStrategy() bool { return pg.turnRollCount >= 3 } func (pg *PigGameData) scoreChaseStrategy() bool { myScore := pg.PlayerScore(pg.player) otherScore := pg.PlayerScore(pg.otherPlayer()) myPendingScore := pg.turnScore + myScore return myPendingScore >= maxScore || myPendingScore > otherScore || pg.turnRollCount >= 5 } func main() { rand.Seed(time.Now().UnixNano()) pg := New() pg.verbose = true strategies := [2]StrategyID{scoreChaseStrat, rollCountStrat} for !pg.GameOver() { pg.Play(strategies[pg.player]) } pg.PrintStatus(gameOverSummary) }
import java.util.Scanner; public class Pigdice { public static void main(String[] args) { Scanner scan = new Scanner(System.in); int players = 0; while(true) { System.out.println("Hello, welcome to Pig Dice the game! How many players? "); if(scan.hasNextInt()) { int nextInt = scan.nextInt(); if(nextInt > 0) { players = nextInt; break; } } else { System.out.println("That wasn't an integer. Try again. \n"); scan.next(); } } System.out.println("Alright, starting with " + players + " players. \n"); play(players, scan); scan.close(); } public static void play(int group, Scanner scan) { final int STRATEGIES = 5; Dice dice = new Dice(); Player[] players = new Player[group]; for(int count = 0; count < group; count++) { players[count] = new Player(count); System.out.println("Player " + players[count].getNumber() + " is alive! "); } System.out.println("Each strategy is numbered 0 - " + (STRATEGIES - 1) + ". They are as follows: "); System.out.println(">> Enter '0' for a human player. "); System.out.println(">> Strategy 1 is a basic strategy where the AI rolls until 20+ points and holds unless the current max is 75+."); System.out.println(">> Strategy 2 is a basic strategy where the AI, after 3 successful rolls, will randomly decide to roll or hold. "); System.out.println(">> Strategy 3 is similar to strategy 2, except it's a little gutsier and will attempt 5 successful rolls. "); System.out.println(">> Strategy 4 is like a mix between strategies 1 and 3. After turn points are >= 20 and while max points are still less than 75, it will randomly hold or roll. "); for(Player player : players) { System.out.println("\nWhat strategy would you like player " + player.getNumber() + " to use? "); while(true) { if(scan.hasNextInt()) { int nextInt = scan.nextInt(); if (nextInt < Strategy.STRATEGIES.length) { player.setStrategy(Strategy.STRATEGIES[nextInt]); break; } } else { System.out.println("That wasn't an option. Try again. "); scan.next(); } } } int max = 0; while(max < 100) { for(Player player : players) { System.out.println(">> Beginning Player " + player.getNumber() + "'s turn. "); player.setTurnPoints(0); player.setMax(max); while(true) { Move choice = player.choose(); if(choice == Move.ROLL) { int roll = dice.roll(); System.out.println(" A " + roll + " was rolled. "); player.setTurnPoints(player.getTurnPoints() + roll); player.incIter(); if(roll == 1) { player.setTurnPoints(0); break; } } else { System.out.println(" The player has held. "); break; } } player.addPoints(player.getTurnPoints()); System.out.println(" Player " + player.getNumber() + "'s turn is now over. Their total is " + player.getPoints() + ". \n"); player.resetIter(); if(max < player.getPoints()) { max = player.getPoints(); } if(max >= 100) { System.out.println("Player " + player.getNumber() + " wins with " + max + " points! End scores: "); for(Player p : players) { System.out.println("Player " + p.getNumber() + " had " + p.getPoints() + " points. "); } break; } } } } }
Translate this program into Java but keep the logic exactly as in Go.
package pig import ( "fmt" "math/rand" "time" ) type ( PlayerID int MessageID int StrategyID int PigGameData struct { player PlayerID turnCount int turnRollCount int turnScore int lastRoll int scores [2]int verbose bool } ) const ( gameOver = iota piggedOut rolls pointSpending holds turn gameOverSummary player1 = PlayerID(0) player2 = PlayerID(1) noPlayer = PlayerID(-1) maxScore = 100 scoreChaseStrat = iota rollCountStrat ) func pluralS(n int) string { if n != 1 { return "s" } return "" } func New() *PigGameData { return &PigGameData{0, 0, 0, 0, 0, [2]int{0, 0}, false} } func (pg *PigGameData) statusMessage(id MessageID) string { var msg string switch id { case gameOver: msg = fmt.Sprintf("Game is over after %d turns", pg.turnCount) case piggedOut: msg = fmt.Sprintf(" Pigged out after %d roll%s", pg.turnRollCount, pluralS(pg.turnRollCount)) case rolls: msg = fmt.Sprintf(" Rolls %d", pg.lastRoll) case pointSpending: msg = fmt.Sprintf(" %d point%s pending", pg.turnScore, pluralS(pg.turnScore)) case holds: msg = fmt.Sprintf(" Holds after %d turns, adding %d points for a total of %d", pg.turnRollCount, pg.turnScore, pg.PlayerScore(noPlayer)) case turn: msg = fmt.Sprintf("Player %d's turn:", pg.player+1) case gameOverSummary: msg = fmt.Sprintf("Game over after %d turns\n player 1 %d\n player 2 %d\n", pg.turnCount, pg.PlayerScore(player1), pg.PlayerScore(player2)) } return msg } func (pg *PigGameData) PrintStatus(id MessageID) { if pg.verbose { fmt.Println(pg.statusMessage(id)) } } func (pg *PigGameData) Play(id StrategyID) (keepPlaying bool) { if pg.GameOver() { pg.PrintStatus(gameOver) return false } if pg.turnCount == 0 { pg.player = player2 pg.NextPlayer() } pg.lastRoll = rand.Intn(6) + 1 pg.PrintStatus(rolls) pg.turnRollCount++ if pg.lastRoll == 1 { pg.PrintStatus(piggedOut) pg.NextPlayer() } else { pg.turnScore += pg.lastRoll pg.PrintStatus(pointSpending) success := false switch id { case scoreChaseStrat: success = pg.scoreChaseStrategy() case rollCountStrat: success = pg.rollCountStrategy() } if success { pg.Hold() pg.NextPlayer() } } return true } func (pg *PigGameData) PlayerScore(id PlayerID) int { if id == noPlayer { return pg.scores[pg.player] } return pg.scores[id] } func (pg *PigGameData) GameOver() bool { return pg.scores[player1] >= maxScore || pg.scores[player2] >= maxScore } func (pg *PigGameData) Winner() PlayerID { for index, score := range pg.scores { if score >= maxScore { return PlayerID(index) } } return noPlayer } func (pg *PigGameData) otherPlayer() PlayerID { return 1 - pg.player } func (pg *PigGameData) Hold() { pg.scores[pg.player] += pg.turnScore pg.PrintStatus(holds) pg.turnRollCount, pg.turnScore = 0, 0 } func (pg *PigGameData) NextPlayer() { pg.turnCount++ pg.turnRollCount, pg.turnScore = 0, 0 pg.player = pg.otherPlayer() pg.PrintStatus(turn) } func (pg *PigGameData) rollCountStrategy() bool { return pg.turnRollCount >= 3 } func (pg *PigGameData) scoreChaseStrategy() bool { myScore := pg.PlayerScore(pg.player) otherScore := pg.PlayerScore(pg.otherPlayer()) myPendingScore := pg.turnScore + myScore return myPendingScore >= maxScore || myPendingScore > otherScore || pg.turnRollCount >= 5 } func main() { rand.Seed(time.Now().UnixNano()) pg := New() pg.verbose = true strategies := [2]StrategyID{scoreChaseStrat, rollCountStrat} for !pg.GameOver() { pg.Play(strategies[pg.player]) } pg.PrintStatus(gameOverSummary) }
import java.util.Scanner; public class Pigdice { public static void main(String[] args) { Scanner scan = new Scanner(System.in); int players = 0; while(true) { System.out.println("Hello, welcome to Pig Dice the game! How many players? "); if(scan.hasNextInt()) { int nextInt = scan.nextInt(); if(nextInt > 0) { players = nextInt; break; } } else { System.out.println("That wasn't an integer. Try again. \n"); scan.next(); } } System.out.println("Alright, starting with " + players + " players. \n"); play(players, scan); scan.close(); } public static void play(int group, Scanner scan) { final int STRATEGIES = 5; Dice dice = new Dice(); Player[] players = new Player[group]; for(int count = 0; count < group; count++) { players[count] = new Player(count); System.out.println("Player " + players[count].getNumber() + " is alive! "); } System.out.println("Each strategy is numbered 0 - " + (STRATEGIES - 1) + ". They are as follows: "); System.out.println(">> Enter '0' for a human player. "); System.out.println(">> Strategy 1 is a basic strategy where the AI rolls until 20+ points and holds unless the current max is 75+."); System.out.println(">> Strategy 2 is a basic strategy where the AI, after 3 successful rolls, will randomly decide to roll or hold. "); System.out.println(">> Strategy 3 is similar to strategy 2, except it's a little gutsier and will attempt 5 successful rolls. "); System.out.println(">> Strategy 4 is like a mix between strategies 1 and 3. After turn points are >= 20 and while max points are still less than 75, it will randomly hold or roll. "); for(Player player : players) { System.out.println("\nWhat strategy would you like player " + player.getNumber() + " to use? "); while(true) { if(scan.hasNextInt()) { int nextInt = scan.nextInt(); if (nextInt < Strategy.STRATEGIES.length) { player.setStrategy(Strategy.STRATEGIES[nextInt]); break; } } else { System.out.println("That wasn't an option. Try again. "); scan.next(); } } } int max = 0; while(max < 100) { for(Player player : players) { System.out.println(">> Beginning Player " + player.getNumber() + "'s turn. "); player.setTurnPoints(0); player.setMax(max); while(true) { Move choice = player.choose(); if(choice == Move.ROLL) { int roll = dice.roll(); System.out.println(" A " + roll + " was rolled. "); player.setTurnPoints(player.getTurnPoints() + roll); player.incIter(); if(roll == 1) { player.setTurnPoints(0); break; } } else { System.out.println(" The player has held. "); break; } } player.addPoints(player.getTurnPoints()); System.out.println(" Player " + player.getNumber() + "'s turn is now over. Their total is " + player.getPoints() + ". \n"); player.resetIter(); if(max < player.getPoints()) { max = player.getPoints(); } if(max >= 100) { System.out.println("Player " + player.getNumber() + " wins with " + max + " points! End scores: "); for(Player p : players) { System.out.println("Player " + p.getNumber() + " had " + p.getPoints() + " points. "); } break; } } } } }
Translate this program into Java but keep the logic exactly as in Go.
package main import ( "flag" "fmt" "math" "math/big" "os" ) var maxRev = big.NewInt(math.MaxUint64 / 10) var ten = big.NewInt(10) func reverseInt(v *big.Int, result *big.Int) *big.Int { if v.Cmp(maxRev) <= 0 { result.SetUint64(reverseUint64(v.Uint64())) } else { if true { s := reverseString(v.String()) result.SetString(s, 10) } else { v := new(big.Int).Set(v) digit := new(big.Int) result.SetUint64(0) for v.BitLen() > 0 { v.QuoRem(v, ten, digit) result.Mul(result, ten) result.Add(result, digit) } } } return result } func reverseUint64(v uint64) uint64 { var r uint64 for v > 0 { r *= 10 r += v % 10 v /= 10 } return r } func reverseString(s string) string { b := make([]byte, len(s)) for i, j := 0, len(s)-1; j >= 0; i, j = i+1, j-1 { b[i] = s[j] } return string(b) } var known = make(map[string]bool) func Lychrel(n uint64, iter uint) (isLychrel, isSeed bool) { v, r := new(big.Int).SetUint64(n), new(big.Int) reverseInt(v, r) seen := make(map[string]bool) isLychrel = true isSeed = true for i := iter; i > 0; i-- { str := v.String() if seen[str] { isLychrel = true break } if ans, ok := known[str]; ok { isLychrel = ans isSeed = false break } seen[str] = true v = v.Add(v, r) reverseInt(v, r) if v.Cmp(r) == 0 { isLychrel = false isSeed = false break } } for k := range seen { known[k] = isLychrel } return isLychrel, isSeed } func main() { max := flag.Uint64("max", 10000, "search in the range 1..`N` inclusive") iter := flag.Uint("iter", 500, "limit palindrome search to `N` iterations") flag.Parse() if flag.NArg() != 0 { flag.Usage() os.Exit(2) } fmt.Printf("Calculating using n = 1..%v and %v iterations:\n", *max, *iter) var seeds []uint64 var related int var pals []uint64 for i := uint64(1); i <= *max; i++ { if l, s := Lychrel(i, *iter); l { if s { seeds = append(seeds, i) } else { related++ } if i == reverseUint64(i) { pals = append(pals, i) } } } fmt.Println(" Number of Lychrel seeds:", len(seeds)) fmt.Println(" Lychrel seeds:", seeds) fmt.Println(" Number of related:", related) fmt.Println("Number of Lychrel palindromes:", len(pals)) fmt.Println(" Lychrel palindromes:", pals) }
import java.math.BigInteger; import java.util.*; public class Lychrel { static Map<BigInteger, Tuple> cache = new HashMap<>(); static class Tuple { final Boolean flag; final BigInteger bi; Tuple(boolean f, BigInteger b) { flag = f; bi = b; } } static BigInteger rev(BigInteger bi) { String s = new StringBuilder(bi.toString()).reverse().toString(); return new BigInteger(s); } static Tuple lychrel(BigInteger n) { Tuple res; if ((res = cache.get(n)) != null) return res; BigInteger r = rev(n); res = new Tuple(true, n); List<BigInteger> seen = new ArrayList<>(); for (int i = 0; i < 500; i++) { n = n.add(r); r = rev(n); if (n.equals(r)) { res = new Tuple(false, BigInteger.ZERO); break; } if (cache.containsKey(n)) { res = cache.get(n); break; } seen.add(n); } for (BigInteger bi : seen) cache.put(bi, res); return res; } public static void main(String[] args) { List<BigInteger> seeds = new ArrayList<>(); List<BigInteger> related = new ArrayList<>(); List<BigInteger> palin = new ArrayList<>(); for (int i = 1; i <= 10_000; i++) { BigInteger n = BigInteger.valueOf(i); Tuple t = lychrel(n); if (!t.flag) continue; if (n.equals(t.bi)) seeds.add(t.bi); else related.add(t.bi); if (n.equals(t.bi)) palin.add(t.bi); } System.out.printf("%d Lychrel seeds: %s%n", seeds.size(), seeds); System.out.printf("%d Lychrel related%n", related.size()); System.out.printf("%d Lychrel palindromes: %s%n", palin.size(), palin); } }
Convert this Go snippet to Java and keep its semantics consistent.
package main import ( "flag" "fmt" "math" "math/big" "os" ) var maxRev = big.NewInt(math.MaxUint64 / 10) var ten = big.NewInt(10) func reverseInt(v *big.Int, result *big.Int) *big.Int { if v.Cmp(maxRev) <= 0 { result.SetUint64(reverseUint64(v.Uint64())) } else { if true { s := reverseString(v.String()) result.SetString(s, 10) } else { v := new(big.Int).Set(v) digit := new(big.Int) result.SetUint64(0) for v.BitLen() > 0 { v.QuoRem(v, ten, digit) result.Mul(result, ten) result.Add(result, digit) } } } return result } func reverseUint64(v uint64) uint64 { var r uint64 for v > 0 { r *= 10 r += v % 10 v /= 10 } return r } func reverseString(s string) string { b := make([]byte, len(s)) for i, j := 0, len(s)-1; j >= 0; i, j = i+1, j-1 { b[i] = s[j] } return string(b) } var known = make(map[string]bool) func Lychrel(n uint64, iter uint) (isLychrel, isSeed bool) { v, r := new(big.Int).SetUint64(n), new(big.Int) reverseInt(v, r) seen := make(map[string]bool) isLychrel = true isSeed = true for i := iter; i > 0; i-- { str := v.String() if seen[str] { isLychrel = true break } if ans, ok := known[str]; ok { isLychrel = ans isSeed = false break } seen[str] = true v = v.Add(v, r) reverseInt(v, r) if v.Cmp(r) == 0 { isLychrel = false isSeed = false break } } for k := range seen { known[k] = isLychrel } return isLychrel, isSeed } func main() { max := flag.Uint64("max", 10000, "search in the range 1..`N` inclusive") iter := flag.Uint("iter", 500, "limit palindrome search to `N` iterations") flag.Parse() if flag.NArg() != 0 { flag.Usage() os.Exit(2) } fmt.Printf("Calculating using n = 1..%v and %v iterations:\n", *max, *iter) var seeds []uint64 var related int var pals []uint64 for i := uint64(1); i <= *max; i++ { if l, s := Lychrel(i, *iter); l { if s { seeds = append(seeds, i) } else { related++ } if i == reverseUint64(i) { pals = append(pals, i) } } } fmt.Println(" Number of Lychrel seeds:", len(seeds)) fmt.Println(" Lychrel seeds:", seeds) fmt.Println(" Number of related:", related) fmt.Println("Number of Lychrel palindromes:", len(pals)) fmt.Println(" Lychrel palindromes:", pals) }
import java.math.BigInteger; import java.util.*; public class Lychrel { static Map<BigInteger, Tuple> cache = new HashMap<>(); static class Tuple { final Boolean flag; final BigInteger bi; Tuple(boolean f, BigInteger b) { flag = f; bi = b; } } static BigInteger rev(BigInteger bi) { String s = new StringBuilder(bi.toString()).reverse().toString(); return new BigInteger(s); } static Tuple lychrel(BigInteger n) { Tuple res; if ((res = cache.get(n)) != null) return res; BigInteger r = rev(n); res = new Tuple(true, n); List<BigInteger> seen = new ArrayList<>(); for (int i = 0; i < 500; i++) { n = n.add(r); r = rev(n); if (n.equals(r)) { res = new Tuple(false, BigInteger.ZERO); break; } if (cache.containsKey(n)) { res = cache.get(n); break; } seen.add(n); } for (BigInteger bi : seen) cache.put(bi, res); return res; } public static void main(String[] args) { List<BigInteger> seeds = new ArrayList<>(); List<BigInteger> related = new ArrayList<>(); List<BigInteger> palin = new ArrayList<>(); for (int i = 1; i <= 10_000; i++) { BigInteger n = BigInteger.valueOf(i); Tuple t = lychrel(n); if (!t.flag) continue; if (n.equals(t.bi)) seeds.add(t.bi); else related.add(t.bi); if (n.equals(t.bi)) palin.add(t.bi); } System.out.printf("%d Lychrel seeds: %s%n", seeds.size(), seeds); System.out.printf("%d Lychrel related%n", related.size()); System.out.printf("%d Lychrel palindromes: %s%n", palin.size(), palin); } }
Generate an equivalent Java version of this Go code.
package main import ( "fmt" "math" "rcu" ) var limit = int(math.Log(1e6) * 1e6 * 1.2) var primes = rcu.Primes(limit) var prevCats = make(map[int]int) func cat(p int) int { if v, ok := prevCats[p]; ok { return v } pf := rcu.PrimeFactors(p + 1) all := true for _, f := range pf { if f != 2 && f != 3 { all = false break } } if all { return 1 } if p > 2 { len := len(pf) for i := len - 1; i >= 1; i-- { if pf[i-1] == pf[i] { pf = append(pf[:i], pf[i+1:]...) } } } for c := 2; c <= 11; c++ { all := true for _, f := range pf { if cat(f) >= c { all = false break } } if all { prevCats[p] = c return c } } return 12 } func main() { es := make([][]int, 12) fmt.Println("First 200 primes:\n") for _, p := range primes[0:200] { c := cat(p) es[c-1] = append(es[c-1], p) } for c := 1; c <= 6; c++ { if len(es[c-1]) > 0 { fmt.Println("Category", c, "\b:") fmt.Println(es[c-1]) fmt.Println() } } fmt.Println("First million primes:\n") for _, p := range primes[200:1e6] { c := cat(p) es[c-1] = append(es[c-1], p) } for c := 1; c <= 12; c++ { e := es[c-1] if len(e) > 0 { format := "Category %-2d: First = %7d Last = %8d Count = %6d\n" fmt.Printf(format, c, e[0], e[len(e)-1], len(e)) } } }
import java.util.*; public class ErdosSelfridge { private int[] primes; private int[] category; public static void main(String[] args) { ErdosSelfridge es = new ErdosSelfridge(1000000); System.out.println("First 200 primes:"); for (var e : es.getPrimesByCategory(200).entrySet()) { int category = e.getKey(); List<Integer> primes = e.getValue(); System.out.printf("Category %d:\n", category); for (int i = 0, n = primes.size(); i != n; ++i) System.out.printf("%4d%c", primes.get(i), (i + 1) % 15 == 0 ? '\n' : ' '); System.out.printf("\n\n"); } System.out.println("First 1,000,000 primes:"); for (var e : es.getPrimesByCategory(1000000).entrySet()) { int category = e.getKey(); List<Integer> primes = e.getValue(); System.out.printf("Category %2d: first = %7d last = %8d count = %d\n", category, primes.get(0), primes.get(primes.size() - 1), primes.size()); } } private ErdosSelfridge(int limit) { PrimeGenerator primeGen = new PrimeGenerator(100000, 200000); List<Integer> primeList = new ArrayList<>(); for (int i = 0; i < limit; ++i) primeList.add(primeGen.nextPrime()); primes = new int[primeList.size()]; for (int i = 0; i < primes.length; ++i) primes[i] = primeList.get(i); category = new int[primes.length]; } private Map<Integer, List<Integer>> getPrimesByCategory(int limit) { Map<Integer, List<Integer>> result = new TreeMap<>(); for (int i = 0; i < limit; ++i) { var p = result.computeIfAbsent(getCategory(i), k -> new ArrayList<Integer>()); p.add(primes[i]); } return result; } private int getCategory(int index) { if (category[index] != 0) return category[index]; int maxCategory = 0; int n = primes[index] + 1; for (int i = 0; n > 1; ++i) { int p = primes[i]; if (p * p > n) break; int count = 0; for (; n % p == 0; ++count) n /= p; if (count != 0) { int category = (p <= 3) ? 1 : 1 + getCategory(i); maxCategory = Math.max(maxCategory, category); } } if (n > 1) { int category = (n <= 3) ? 1 : 1 + getCategory(getIndex(n)); maxCategory = Math.max(maxCategory, category); } category[index] = maxCategory; return maxCategory; } private int getIndex(int prime) { return Arrays.binarySearch(primes, prime); } }
Translate this program into Java but keep the logic exactly as in Go.
package main import ( "github.com/fogleman/gg" "github.com/trubitsyn/go-lindenmayer" "log" "math" ) const twoPi = 2 * math.Pi var ( width = 770.0 height = 770.0 dc = gg.NewContext(int(width), int(height)) ) var cx, cy, h, theta float64 func main() { dc.SetRGB(0, 0, 1) dc.Clear() cx, cy = 10, height/2+5 h = 6 sys := lindenmayer.Lsystem{ Variables: []rune{'X'}, Constants: []rune{'F', '+', '-'}, Axiom: "F+XF+F+XF", Rules: []lindenmayer.Rule{ {"X", "XF-F+F-XF+F+XF-F+F-X"}, }, Angle: math.Pi / 2, } result := lindenmayer.Iterate(&sys, 5) operations := map[rune]func(){ 'F': func() { newX, newY := cx+h*math.Sin(theta), cy-h*math.Cos(theta) dc.LineTo(newX, newY) cx, cy = newX, newY }, '+': func() { theta = math.Mod(theta+sys.Angle, twoPi) }, '-': func() { theta = math.Mod(theta-sys.Angle, twoPi) }, } if err := lindenmayer.Process(result, operations); err != nil { log.Fatal(err) } operations['+']() operations['F']() dc.SetRGB255(255, 255, 0) dc.SetLineWidth(2) dc.Stroke() dc.SavePNG("sierpinski_square_curve.png") }
import java.io.*; public class SierpinskiSquareCurve { public static void main(final String[] args) { try (Writer writer = new BufferedWriter(new FileWriter("sierpinski_square.svg"))) { SierpinskiSquareCurve s = new SierpinskiSquareCurve(writer); int size = 635, length = 5; s.currentAngle = 0; s.currentX = (size - length)/2; s.currentY = length; s.lineLength = length; s.begin(size); s.execute(rewrite(5)); s.end(); } catch (final Exception ex) { ex.printStackTrace(); } } private SierpinskiSquareCurve(final Writer writer) { this.writer = writer; } private void begin(final int size) throws IOException { write("<svg xmlns='http: write("<rect width='100%%' height='100%%' fill='white'/>\n"); write("<path stroke-width='1' stroke='black' fill='none' d='"); } private void end() throws IOException { write("'/>\n</svg>\n"); } private void execute(final String s) throws IOException { write("M%g,%g\n", currentX, currentY); for (int i = 0, n = s.length(); i < n; ++i) { switch (s.charAt(i)) { case 'F': line(lineLength); break; case '+': turn(ANGLE); break; case '-': turn(-ANGLE); break; } } } private void line(final double length) throws IOException { final double theta = (Math.PI * currentAngle) / 180.0; currentX += length * Math.cos(theta); currentY += length * Math.sin(theta); write("L%g,%g\n", currentX, currentY); } private void turn(final int angle) { currentAngle = (currentAngle + angle) % 360; } private void write(final String format, final Object... args) throws IOException { writer.write(String.format(format, args)); } private static String rewrite(final int order) { String s = AXIOM; for (int i = 0; i < order; ++i) { final StringBuilder sb = new StringBuilder(); for (int j = 0, n = s.length(); j < n; ++j) { final char ch = s.charAt(j); if (ch == 'X') sb.append(PRODUCTION); else sb.append(ch); } s = sb.toString(); } return s; } private final Writer writer; private double lineLength; private double currentX; private double currentY; private int currentAngle; private static final String AXIOM = "F+XF+F+XF"; private static final String PRODUCTION = "XF-F+F-XF+F+XF-F+F-X"; private static final int ANGLE = 90; }
Please provide an equivalent version of this Go code in Java.
package main import ( "github.com/fogleman/gg" "github.com/trubitsyn/go-lindenmayer" "log" "math" ) const twoPi = 2 * math.Pi var ( width = 770.0 height = 770.0 dc = gg.NewContext(int(width), int(height)) ) var cx, cy, h, theta float64 func main() { dc.SetRGB(0, 0, 1) dc.Clear() cx, cy = 10, height/2+5 h = 6 sys := lindenmayer.Lsystem{ Variables: []rune{'X'}, Constants: []rune{'F', '+', '-'}, Axiom: "F+XF+F+XF", Rules: []lindenmayer.Rule{ {"X", "XF-F+F-XF+F+XF-F+F-X"}, }, Angle: math.Pi / 2, } result := lindenmayer.Iterate(&sys, 5) operations := map[rune]func(){ 'F': func() { newX, newY := cx+h*math.Sin(theta), cy-h*math.Cos(theta) dc.LineTo(newX, newY) cx, cy = newX, newY }, '+': func() { theta = math.Mod(theta+sys.Angle, twoPi) }, '-': func() { theta = math.Mod(theta-sys.Angle, twoPi) }, } if err := lindenmayer.Process(result, operations); err != nil { log.Fatal(err) } operations['+']() operations['F']() dc.SetRGB255(255, 255, 0) dc.SetLineWidth(2) dc.Stroke() dc.SavePNG("sierpinski_square_curve.png") }
import java.io.*; public class SierpinskiSquareCurve { public static void main(final String[] args) { try (Writer writer = new BufferedWriter(new FileWriter("sierpinski_square.svg"))) { SierpinskiSquareCurve s = new SierpinskiSquareCurve(writer); int size = 635, length = 5; s.currentAngle = 0; s.currentX = (size - length)/2; s.currentY = length; s.lineLength = length; s.begin(size); s.execute(rewrite(5)); s.end(); } catch (final Exception ex) { ex.printStackTrace(); } } private SierpinskiSquareCurve(final Writer writer) { this.writer = writer; } private void begin(final int size) throws IOException { write("<svg xmlns='http: write("<rect width='100%%' height='100%%' fill='white'/>\n"); write("<path stroke-width='1' stroke='black' fill='none' d='"); } private void end() throws IOException { write("'/>\n</svg>\n"); } private void execute(final String s) throws IOException { write("M%g,%g\n", currentX, currentY); for (int i = 0, n = s.length(); i < n; ++i) { switch (s.charAt(i)) { case 'F': line(lineLength); break; case '+': turn(ANGLE); break; case '-': turn(-ANGLE); break; } } } private void line(final double length) throws IOException { final double theta = (Math.PI * currentAngle) / 180.0; currentX += length * Math.cos(theta); currentY += length * Math.sin(theta); write("L%g,%g\n", currentX, currentY); } private void turn(final int angle) { currentAngle = (currentAngle + angle) % 360; } private void write(final String format, final Object... args) throws IOException { writer.write(String.format(format, args)); } private static String rewrite(final int order) { String s = AXIOM; for (int i = 0; i < order; ++i) { final StringBuilder sb = new StringBuilder(); for (int j = 0, n = s.length(); j < n; ++j) { final char ch = s.charAt(j); if (ch == 'X') sb.append(PRODUCTION); else sb.append(ch); } s = sb.toString(); } return s; } private final Writer writer; private double lineLength; private double currentX; private double currentY; private int currentAngle; private static final String AXIOM = "F+XF+F+XF"; private static final String PRODUCTION = "XF-F+F-XF+F+XF-F+F-X"; private static final int ANGLE = 90; }
Convert this Go block to Java, preserving its control flow and logic.
package main import ( "fmt" "math" "sort" ) const adj = 0.0001 var primes = []uint64{ 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, } func gcd(x, y uint64) uint64 { for y != 0 { x, y = y, x%y } return x } func isSquareFree(x uint64) bool { for _, p := range primes { p2 := p * p if p2 > x { break } if x%p2 == 0 { return false } } return true } func iroot(x, p uint64) uint64 { return uint64(math.Pow(float64(x), 1.0/float64(p)) + adj) } func ipow(x, p uint64) uint64 { prod := uint64(1) for p > 0 { if p&1 != 0 { prod *= x } p >>= 1 x *= x } return prod } func powerful(n, k uint64) []uint64 { set := make(map[uint64]bool) var f func(m, r uint64) f = func(m, r uint64) { if r < k { set[m] = true return } for v := uint64(1); v <= iroot(n/m, r); v++ { if r > k { if !isSquareFree(v) || gcd(m, v) != 1 { continue } } f(m*ipow(v, r), r-1) } } f(1, (1<<k)-1) list := make([]uint64, 0, len(set)) for key := range set { list = append(list, key) } sort.Slice(list, func(i, j int) bool { return list[i] < list[j] }) return list } func main() { power := uint64(10) for k := uint64(2); k <= 10; k++ { power *= 10 a := powerful(power, k) le := len(a) h, t := a[0:5], a[le-5:] fmt.Printf("%d %2d-powerful numbers <= 10^%-2d: %v ... %v\n", le, k, k, h, t) } fmt.Println() for k := uint64(2); k <= 10; k++ { power := uint64(1) var counts []int for j := uint64(0); j < k+10; j++ { a := powerful(power, k) counts = append(counts, len(a)) power *= 10 } j := k + 10 fmt.Printf("Count of %2d-powerful numbers <= 10^j, j in [0, %d): %v\n", k, j, counts) } }
import java.math.BigInteger; import java.util.ArrayList; import java.util.Collections; import java.util.HashSet; import java.util.List; import java.util.Set; public class PowerfulNumbers { public static void main(String[] args) { System.out.printf("Task: For k = 2..10, generate the set of k-powerful numbers <= 10^k and show the first 5 and the last 5 terms, along with the length of the set%n"); for ( int k = 2 ; k <= 10 ; k++ ) { BigInteger max = BigInteger.valueOf(10).pow(k); List<BigInteger> powerfulNumbers = getPowerFulNumbers(max, k); System.out.printf("There are %d %d-powerful numbers between 1 and %d. %nList: %s%n", powerfulNumbers.size(), k, max, getList(powerfulNumbers)); } System.out.printf("%nTask: For k = 2..10, show the number of k-powerful numbers less than or equal to 10^j, for 0 <= j < k+10%n"); for ( int k = 2 ; k <= 10 ; k++ ) { List<Integer> powCount = new ArrayList<>(); for ( int j = 0 ; j < k+10 ; j++ ) { BigInteger max = BigInteger.valueOf(10).pow(j); powCount.add(countPowerFulNumbers(max, k)); } System.out.printf("Count of %2d-powerful numbers <= 10^j, j in [0, %d]: %s%n", k, k+9, powCount); } } private static String getList(List<BigInteger> list) { StringBuilder sb = new StringBuilder(); sb.append(list.subList(0, 5).toString().replace("]", "")); sb.append(" ... "); sb.append(list.subList(list.size()-5, list.size()).toString().replace("[", "")); return sb.toString(); } private static int countPowerFulNumbers(BigInteger max, int k) { return potentialPowerful(max, k).size(); } private static List<BigInteger> getPowerFulNumbers(BigInteger max, int k) { List<BigInteger> powerfulNumbers = new ArrayList<>(potentialPowerful(max, k)); Collections.sort(powerfulNumbers); return powerfulNumbers; } private static Set<BigInteger> potentialPowerful(BigInteger max, int k) { int[] indexes = new int[k]; for ( int i = 0 ; i < k ; i++ ) { indexes[i] = 1; } Set<BigInteger> powerful = new HashSet<>(); boolean foundPower = true; while ( foundPower ) { boolean genPowerful = false; for ( int index = 0 ; index < k ; index++ ) { BigInteger power = BigInteger.ONE; for ( int i = 0 ; i < k ; i++ ) { power = power.multiply(BigInteger.valueOf(indexes[i]).pow(k+i)); } if ( power.compareTo(max) <= 0 ) { powerful.add(power); indexes[0] += 1; genPowerful = true; break; } else { indexes[index] = 1; if ( index < k-1 ) { indexes[index+1] += 1; } } } if ( ! genPowerful ) { foundPower = false; } } return powerful; } }
Write a version of this Go function in Java with identical behavior.
package main import ( "fmt" "math" "sort" ) const adj = 0.0001 var primes = []uint64{ 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, } func gcd(x, y uint64) uint64 { for y != 0 { x, y = y, x%y } return x } func isSquareFree(x uint64) bool { for _, p := range primes { p2 := p * p if p2 > x { break } if x%p2 == 0 { return false } } return true } func iroot(x, p uint64) uint64 { return uint64(math.Pow(float64(x), 1.0/float64(p)) + adj) } func ipow(x, p uint64) uint64 { prod := uint64(1) for p > 0 { if p&1 != 0 { prod *= x } p >>= 1 x *= x } return prod } func powerful(n, k uint64) []uint64 { set := make(map[uint64]bool) var f func(m, r uint64) f = func(m, r uint64) { if r < k { set[m] = true return } for v := uint64(1); v <= iroot(n/m, r); v++ { if r > k { if !isSquareFree(v) || gcd(m, v) != 1 { continue } } f(m*ipow(v, r), r-1) } } f(1, (1<<k)-1) list := make([]uint64, 0, len(set)) for key := range set { list = append(list, key) } sort.Slice(list, func(i, j int) bool { return list[i] < list[j] }) return list } func main() { power := uint64(10) for k := uint64(2); k <= 10; k++ { power *= 10 a := powerful(power, k) le := len(a) h, t := a[0:5], a[le-5:] fmt.Printf("%d %2d-powerful numbers <= 10^%-2d: %v ... %v\n", le, k, k, h, t) } fmt.Println() for k := uint64(2); k <= 10; k++ { power := uint64(1) var counts []int for j := uint64(0); j < k+10; j++ { a := powerful(power, k) counts = append(counts, len(a)) power *= 10 } j := k + 10 fmt.Printf("Count of %2d-powerful numbers <= 10^j, j in [0, %d): %v\n", k, j, counts) } }
import java.math.BigInteger; import java.util.ArrayList; import java.util.Collections; import java.util.HashSet; import java.util.List; import java.util.Set; public class PowerfulNumbers { public static void main(String[] args) { System.out.printf("Task: For k = 2..10, generate the set of k-powerful numbers <= 10^k and show the first 5 and the last 5 terms, along with the length of the set%n"); for ( int k = 2 ; k <= 10 ; k++ ) { BigInteger max = BigInteger.valueOf(10).pow(k); List<BigInteger> powerfulNumbers = getPowerFulNumbers(max, k); System.out.printf("There are %d %d-powerful numbers between 1 and %d. %nList: %s%n", powerfulNumbers.size(), k, max, getList(powerfulNumbers)); } System.out.printf("%nTask: For k = 2..10, show the number of k-powerful numbers less than or equal to 10^j, for 0 <= j < k+10%n"); for ( int k = 2 ; k <= 10 ; k++ ) { List<Integer> powCount = new ArrayList<>(); for ( int j = 0 ; j < k+10 ; j++ ) { BigInteger max = BigInteger.valueOf(10).pow(j); powCount.add(countPowerFulNumbers(max, k)); } System.out.printf("Count of %2d-powerful numbers <= 10^j, j in [0, %d]: %s%n", k, k+9, powCount); } } private static String getList(List<BigInteger> list) { StringBuilder sb = new StringBuilder(); sb.append(list.subList(0, 5).toString().replace("]", "")); sb.append(" ... "); sb.append(list.subList(list.size()-5, list.size()).toString().replace("[", "")); return sb.toString(); } private static int countPowerFulNumbers(BigInteger max, int k) { return potentialPowerful(max, k).size(); } private static List<BigInteger> getPowerFulNumbers(BigInteger max, int k) { List<BigInteger> powerfulNumbers = new ArrayList<>(potentialPowerful(max, k)); Collections.sort(powerfulNumbers); return powerfulNumbers; } private static Set<BigInteger> potentialPowerful(BigInteger max, int k) { int[] indexes = new int[k]; for ( int i = 0 ; i < k ; i++ ) { indexes[i] = 1; } Set<BigInteger> powerful = new HashSet<>(); boolean foundPower = true; while ( foundPower ) { boolean genPowerful = false; for ( int index = 0 ; index < k ; index++ ) { BigInteger power = BigInteger.ONE; for ( int i = 0 ; i < k ; i++ ) { power = power.multiply(BigInteger.valueOf(indexes[i]).pow(k+i)); } if ( power.compareTo(max) <= 0 ) { powerful.add(power); indexes[0] += 1; genPowerful = true; break; } else { indexes[index] = 1; if ( index < k-1 ) { indexes[index+1] += 1; } } } if ( ! genPowerful ) { foundPower = false; } } return powerful; } }
Port the provided Go code into Java while preserving the original functionality.
package main import ( "fmt" "math/big" ) func div(dividend, divisor []*big.Rat) (quotient, remainder []*big.Rat) { out := make([]*big.Rat, len(dividend)) for i, c := range dividend { out[i] = new(big.Rat).Set(c) } for i := 0; i < len(dividend)-(len(divisor)-1); i++ { out[i].Quo(out[i], divisor[0]) if coef := out[i]; coef.Sign() != 0 { var a big.Rat for j := 1; j < len(divisor); j++ { out[i+j].Add(out[i+j], a.Mul(a.Neg(divisor[j]), coef)) } } } separator := len(out) - (len(divisor) - 1) return out[:separator], out[separator:] } func main() { N := []*big.Rat{ big.NewRat(1, 1), big.NewRat(-12, 1), big.NewRat(0, 1), big.NewRat(-42, 1)} D := []*big.Rat{big.NewRat(1, 1), big.NewRat(-3, 1)} Q, R := div(N, D) fmt.Printf("%v / %v = %v remainder %v\n", N, D, Q, R) }
import java.util.Arrays; public class Test { public static void main(String[] args) { int[] N = {1, -12, 0, -42}; int[] D = {1, -3}; System.out.printf("%s / %s = %s", Arrays.toString(N), Arrays.toString(D), Arrays.deepToString(extendedSyntheticDivision(N, D))); } static int[][] extendedSyntheticDivision(int[] dividend, int[] divisor) { int[] out = dividend.clone(); int normalizer = divisor[0]; for (int i = 0; i < dividend.length - (divisor.length - 1); i++) { out[i] /= normalizer; int coef = out[i]; if (coef != 0) { for (int j = 1; j < divisor.length; j++) out[i + j] += -divisor[j] * coef; } } int separator = out.length - (divisor.length - 1); return new int[][]{ Arrays.copyOfRange(out, 0, separator), Arrays.copyOfRange(out, separator, out.length) }; } }
Write the same code in Java as shown below in Go.
package main import ( "fmt" "math/big" ) func div(dividend, divisor []*big.Rat) (quotient, remainder []*big.Rat) { out := make([]*big.Rat, len(dividend)) for i, c := range dividend { out[i] = new(big.Rat).Set(c) } for i := 0; i < len(dividend)-(len(divisor)-1); i++ { out[i].Quo(out[i], divisor[0]) if coef := out[i]; coef.Sign() != 0 { var a big.Rat for j := 1; j < len(divisor); j++ { out[i+j].Add(out[i+j], a.Mul(a.Neg(divisor[j]), coef)) } } } separator := len(out) - (len(divisor) - 1) return out[:separator], out[separator:] } func main() { N := []*big.Rat{ big.NewRat(1, 1), big.NewRat(-12, 1), big.NewRat(0, 1), big.NewRat(-42, 1)} D := []*big.Rat{big.NewRat(1, 1), big.NewRat(-3, 1)} Q, R := div(N, D) fmt.Printf("%v / %v = %v remainder %v\n", N, D, Q, R) }
import java.util.Arrays; public class Test { public static void main(String[] args) { int[] N = {1, -12, 0, -42}; int[] D = {1, -3}; System.out.printf("%s / %s = %s", Arrays.toString(N), Arrays.toString(D), Arrays.deepToString(extendedSyntheticDivision(N, D))); } static int[][] extendedSyntheticDivision(int[] dividend, int[] divisor) { int[] out = dividend.clone(); int normalizer = divisor[0]; for (int i = 0; i < dividend.length - (divisor.length - 1); i++) { out[i] /= normalizer; int coef = out[i]; if (coef != 0) { for (int j = 1; j < divisor.length; j++) out[i + j] += -divisor[j] * coef; } } int separator = out.length - (divisor.length - 1); return new int[][]{ Arrays.copyOfRange(out, 0, separator), Arrays.copyOfRange(out, separator, out.length) }; } }
Generate a Java translation of this Go snippet without changing its computational steps.
package main import ( "bytes" "fmt" "io/ioutil" "log" "sort" "strings" ) func main() { wordList := "unixdict.txt" b, err := ioutil.ReadFile(wordList) if err != nil { log.Fatal("Error reading file") } bwords := bytes.Fields(b) words := make([]string, len(bwords)) for i, bword := range bwords { words[i] = string(bword) } count := 0 fmt.Println("The odd words with length > 4 in", wordList, "are:") for _, word := range words { rword := []rune(word) if len(rword) > 8 { var sb strings.Builder for i := 0; i < len(rword); i += 2 { sb.WriteRune(rword[i]) } s := sb.String() idx := sort.SearchStrings(words, s) if idx < len(words) && words[idx] == s { count = count + 1 fmt.Printf("%2d: %-12s -> %s\n", count, word, s) } } } }
import java.io.*; import java.util.*; public class OddWords { public static void main(String[] args) { try { Set<String> dictionary = new TreeSet<>(); final int minLength = 5; String fileName = "unixdict.txt"; if (args.length != 0) fileName = args[0]; try (BufferedReader reader = new BufferedReader(new FileReader(fileName))) { String line; while ((line = reader.readLine()) != null) { if (line.length() >= minLength) dictionary.add(line); } } StringBuilder word1 = new StringBuilder(); StringBuilder word2 = new StringBuilder(); List<StringPair> evenWords = new ArrayList<>(); List<StringPair> oddWords = new ArrayList<>(); for (String word : dictionary) { int length = word.length(); if (length < minLength + 2 * (minLength/2)) continue; word1.setLength(0); word2.setLength(0); for (int i = 0; i < length; ++i) { if ((i & 1) == 0) word1.append(word.charAt(i)); else word2.append(word.charAt(i)); } String oddWord = word1.toString(); String evenWord = word2.toString(); if (dictionary.contains(oddWord)) oddWords.add(new StringPair(word, oddWord)); if (dictionary.contains(evenWord)) evenWords.add(new StringPair(word, evenWord)); } System.out.println("Odd words:"); printWords(oddWords); System.out.println("\nEven words:"); printWords(evenWords); } catch (Exception e) { e.printStackTrace(); } } private static void printWords(List<StringPair> strings) { int n = 1; for (StringPair pair : strings) { System.out.printf("%2d: %-14s%s\n", n++, pair.string1, pair.string2); } } private static class StringPair { private String string1; private String string2; private StringPair(String s1, String s2) { string1 = s1; string2 = s2; } } }
Translate the given Go code snippet into Java without altering its behavior.
package main import ( "fmt" "github.com/ALTree/bigfloat" "math/big" ) const ( prec = 256 ps = "3.1415926535897932384626433832795028841971693993751058209749445923078164" ) func q(d int64) *big.Float { pi, _ := new(big.Float).SetPrec(prec).SetString(ps) t := new(big.Float).SetPrec(prec).SetInt64(d) t.Sqrt(t) t.Mul(pi, t) return bigfloat.Exp(t) } func main() { fmt.Println("Ramanujan's constant to 32 decimal places is:") fmt.Printf("%.32f\n", q(163)) heegners := [4][2]int64{ {19, 96}, {43, 960}, {67, 5280}, {163, 640320}, } fmt.Println("\nHeegner numbers yielding 'almost' integers:") t := new(big.Float).SetPrec(prec) for _, h := range heegners { qh := q(h[0]) c := h[1]*h[1]*h[1] + 744 t.SetInt64(c) t.Sub(t, qh) fmt.Printf("%3d: %51.32f ≈ %18d (diff: %.32f)\n", h[0], qh, c, t) } }
import java.math.BigDecimal; import java.math.MathContext; import java.util.Arrays; import java.util.List; public class RamanujanConstant { public static void main(String[] args) { System.out.printf("Ramanujan's Constant to 100 digits = %s%n%n", ramanujanConstant(163, 100)); System.out.printf("Heegner numbers yielding 'almost' integers:%n"); List<Integer> heegnerNumbers = Arrays.asList(19, 43, 67, 163); List<Integer> heegnerVals = Arrays.asList(96, 960, 5280, 640320); for ( int i = 0 ; i < heegnerNumbers.size() ; i++ ) { int heegnerNumber = heegnerNumbers.get(i); int heegnerVal = heegnerVals.get(i); BigDecimal integer = BigDecimal.valueOf(heegnerVal).pow(3).add(BigDecimal.valueOf(744)); BigDecimal compute = ramanujanConstant(heegnerNumber, 50); System.out.printf("%3d : %50s ~ %18s (diff ~ %s)%n", heegnerNumber, compute, integer, integer.subtract(compute, new MathContext(30)).toPlainString()); } } public static BigDecimal ramanujanConstant(int sqrt, int digits) { MathContext mc = new MathContext(digits + 5); return bigE(bigPi(mc).multiply(bigSquareRoot(BigDecimal.valueOf(sqrt), mc), mc), mc).round(new MathContext(digits)); } public static BigDecimal bigE(BigDecimal exponent, MathContext mc) { BigDecimal e = BigDecimal.ONE; BigDecimal ak = e; int k = 0; BigDecimal min = BigDecimal.ONE.divide(BigDecimal.TEN.pow(mc.getPrecision())); while ( true ) { k++; ak = ak.multiply(exponent).divide(BigDecimal.valueOf(k), mc); e = e.add(ak, mc); if ( ak.compareTo(min) < 0 ) { break; } } return e; } public static BigDecimal bigPi(MathContext mc) { int k = 0; BigDecimal ak = BigDecimal.ONE; BigDecimal a = ak; BigDecimal b = BigDecimal.ZERO; BigDecimal c = BigDecimal.valueOf(640320); BigDecimal c3 = c.pow(3); double digitePerTerm = Math.log10(c.pow(3).divide(BigDecimal.valueOf(24), mc).doubleValue()) - Math.log10(72); double digits = 0; while ( digits < mc.getPrecision() ) { k++; digits += digitePerTerm; BigDecimal top = BigDecimal.valueOf(-24).multiply(BigDecimal.valueOf(6*k-5)).multiply(BigDecimal.valueOf(2*k-1)).multiply(BigDecimal.valueOf(6*k-1)); BigDecimal term = top.divide(BigDecimal.valueOf(k*k*k).multiply(c3), mc); ak = ak.multiply(term, mc); a = a.add(ak, mc); b = b.add(BigDecimal.valueOf(k).multiply(ak, mc), mc); } BigDecimal total = BigDecimal.valueOf(13591409).multiply(a, mc).add(BigDecimal.valueOf(545140134).multiply(b, mc), mc); return BigDecimal.valueOf(426880).multiply(bigSquareRoot(BigDecimal.valueOf(10005), mc), mc).divide(total, mc); } public static BigDecimal bigSquareRoot(BigDecimal squareDecimal, MathContext mc) { double sqrt = Math.sqrt(squareDecimal.doubleValue()); BigDecimal x0 = new BigDecimal(sqrt, mc); BigDecimal two = BigDecimal.valueOf(2); while ( true ) { BigDecimal x1 = x0.subtract(x0.multiply(x0, mc).subtract(squareDecimal).divide(two.multiply(x0, mc), mc), mc); String x1String = x1.toPlainString(); String x0String = x0.toPlainString(); if ( x1String.substring(0, x1String.length()-1).compareTo(x0String.substring(0, x0String.length()-1)) == 0 ) { break; } x0 = x1; } return x0; } }
Produce a language-to-language conversion: from Go to Java, same semantics.
package main import ( "fmt" "github.com/ALTree/bigfloat" "math/big" ) const ( prec = 256 ps = "3.1415926535897932384626433832795028841971693993751058209749445923078164" ) func q(d int64) *big.Float { pi, _ := new(big.Float).SetPrec(prec).SetString(ps) t := new(big.Float).SetPrec(prec).SetInt64(d) t.Sqrt(t) t.Mul(pi, t) return bigfloat.Exp(t) } func main() { fmt.Println("Ramanujan's constant to 32 decimal places is:") fmt.Printf("%.32f\n", q(163)) heegners := [4][2]int64{ {19, 96}, {43, 960}, {67, 5280}, {163, 640320}, } fmt.Println("\nHeegner numbers yielding 'almost' integers:") t := new(big.Float).SetPrec(prec) for _, h := range heegners { qh := q(h[0]) c := h[1]*h[1]*h[1] + 744 t.SetInt64(c) t.Sub(t, qh) fmt.Printf("%3d: %51.32f ≈ %18d (diff: %.32f)\n", h[0], qh, c, t) } }
import java.math.BigDecimal; import java.math.MathContext; import java.util.Arrays; import java.util.List; public class RamanujanConstant { public static void main(String[] args) { System.out.printf("Ramanujan's Constant to 100 digits = %s%n%n", ramanujanConstant(163, 100)); System.out.printf("Heegner numbers yielding 'almost' integers:%n"); List<Integer> heegnerNumbers = Arrays.asList(19, 43, 67, 163); List<Integer> heegnerVals = Arrays.asList(96, 960, 5280, 640320); for ( int i = 0 ; i < heegnerNumbers.size() ; i++ ) { int heegnerNumber = heegnerNumbers.get(i); int heegnerVal = heegnerVals.get(i); BigDecimal integer = BigDecimal.valueOf(heegnerVal).pow(3).add(BigDecimal.valueOf(744)); BigDecimal compute = ramanujanConstant(heegnerNumber, 50); System.out.printf("%3d : %50s ~ %18s (diff ~ %s)%n", heegnerNumber, compute, integer, integer.subtract(compute, new MathContext(30)).toPlainString()); } } public static BigDecimal ramanujanConstant(int sqrt, int digits) { MathContext mc = new MathContext(digits + 5); return bigE(bigPi(mc).multiply(bigSquareRoot(BigDecimal.valueOf(sqrt), mc), mc), mc).round(new MathContext(digits)); } public static BigDecimal bigE(BigDecimal exponent, MathContext mc) { BigDecimal e = BigDecimal.ONE; BigDecimal ak = e; int k = 0; BigDecimal min = BigDecimal.ONE.divide(BigDecimal.TEN.pow(mc.getPrecision())); while ( true ) { k++; ak = ak.multiply(exponent).divide(BigDecimal.valueOf(k), mc); e = e.add(ak, mc); if ( ak.compareTo(min) < 0 ) { break; } } return e; } public static BigDecimal bigPi(MathContext mc) { int k = 0; BigDecimal ak = BigDecimal.ONE; BigDecimal a = ak; BigDecimal b = BigDecimal.ZERO; BigDecimal c = BigDecimal.valueOf(640320); BigDecimal c3 = c.pow(3); double digitePerTerm = Math.log10(c.pow(3).divide(BigDecimal.valueOf(24), mc).doubleValue()) - Math.log10(72); double digits = 0; while ( digits < mc.getPrecision() ) { k++; digits += digitePerTerm; BigDecimal top = BigDecimal.valueOf(-24).multiply(BigDecimal.valueOf(6*k-5)).multiply(BigDecimal.valueOf(2*k-1)).multiply(BigDecimal.valueOf(6*k-1)); BigDecimal term = top.divide(BigDecimal.valueOf(k*k*k).multiply(c3), mc); ak = ak.multiply(term, mc); a = a.add(ak, mc); b = b.add(BigDecimal.valueOf(k).multiply(ak, mc), mc); } BigDecimal total = BigDecimal.valueOf(13591409).multiply(a, mc).add(BigDecimal.valueOf(545140134).multiply(b, mc), mc); return BigDecimal.valueOf(426880).multiply(bigSquareRoot(BigDecimal.valueOf(10005), mc), mc).divide(total, mc); } public static BigDecimal bigSquareRoot(BigDecimal squareDecimal, MathContext mc) { double sqrt = Math.sqrt(squareDecimal.doubleValue()); BigDecimal x0 = new BigDecimal(sqrt, mc); BigDecimal two = BigDecimal.valueOf(2); while ( true ) { BigDecimal x1 = x0.subtract(x0.multiply(x0, mc).subtract(squareDecimal).divide(two.multiply(x0, mc), mc), mc); String x1String = x1.toPlainString(); String x0String = x0.toPlainString(); if ( x1String.substring(0, x1String.length()-1).compareTo(x0String.substring(0, x0String.length()-1)) == 0 ) { break; } x0 = x1; } return x0; } }
Rewrite this program in Java while keeping its functionality equivalent to the Go version.
package main import ( "fmt" "strings" ) type dict map[string]bool func newDict(words ...string) dict { d := dict{} for _, w := range words { d[w] = true } return d } func (d dict) wordBreak(s string) (broken []string, ok bool) { if s == "" { return nil, true } type prefix struct { length int broken []string } bp := []prefix{{0, nil}} for end := 1; end <= len(s); end++ { for i := len(bp) - 1; i >= 0; i-- { w := s[bp[i].length:end] if d[w] { b := append(bp[i].broken, w) if end == len(s) { return b, true } bp = append(bp, prefix{end, b}) break } } } return nil, false } func main() { d := newDict("a", "bc", "abc", "cd", "b") for _, s := range []string{"abcd", "abbc", "abcbcd", "acdbc", "abcdd"} { if b, ok := d.wordBreak(s); ok { fmt.Printf("%s: %s\n", s, strings.Join(b, " ")) } else { fmt.Println("can't break") } } }
import java.util.ArrayList; import java.util.Arrays; import java.util.LinkedList; import java.util.List; import java.util.Queue; public class WordBreak { public static void main(String[] args) { List<String> dict = Arrays.asList("a", "aa", "b", "ab", "aab"); for ( String testString : Arrays.asList("aab", "aa b") ) { List<List<String>> matches = wordBreak(testString, dict); System.out.printf("String = %s, Dictionary = %s. Solutions = %d:%n", testString, dict, matches.size()); for ( List<String> match : matches ) { System.out.printf(" Word Break = %s%n", match); } System.out.printf("%n"); } dict = Arrays.asList("abc", "a", "ac", "b", "c", "cb", "d"); for ( String testString : Arrays.asList("abcd", "abbc", "abcbcd", "acdbc", "abcdd") ) { List<List<String>> matches = wordBreak(testString, dict); System.out.printf("String = %s, Dictionary = %s. Solutions = %d:%n", testString, dict, matches.size()); for ( List<String> match : matches ) { System.out.printf(" Word Break = %s%n", match); } System.out.printf("%n"); } } private static List<List<String>> wordBreak(String s, List<String> dictionary) { List<List<String>> matches = new ArrayList<>(); Queue<Node> queue = new LinkedList<>(); queue.add(new Node(s)); while ( ! queue.isEmpty() ) { Node node = queue.remove(); if ( node.val.length() == 0 ) { matches.add(node.parsed); } else { for ( String word : dictionary ) { if ( node.val.startsWith(word) ) { String valNew = node.val.substring(word.length(), node.val.length()); List<String> parsedNew = new ArrayList<>(); parsedNew.addAll(node.parsed); parsedNew.add(word); queue.add(new Node(valNew, parsedNew)); } } } } return matches; } private static class Node { private String val; private List<String> parsed; public Node(String initial) { val = initial; parsed = new ArrayList<>(); } public Node(String s, List<String> p) { val = s; parsed = p; } } }
Translate this program into Java but keep the logic exactly as in Go.
package main import ( "fmt" "math" "rcu" "sort" ) var primes = rcu.Primes(1e8 - 1) type res struct { bc interface{} next int } func getBrilliant(digits, limit int, countOnly bool) res { var brilliant []int count := 0 pow := 1 next := math.MaxInt for k := 1; k <= digits; k++ { var s []int for _, p := range primes { if p >= pow*10 { break } if p > pow { s = append(s, p) } } for i := 0; i < len(s); i++ { for j := i; j < len(s); j++ { prod := s[i] * s[j] if prod < limit { if countOnly { count++ } else { brilliant = append(brilliant, prod) } } else { if next > prod { next = prod } break } } } pow *= 10 } if countOnly { return res{count, next} } return res{brilliant, next} } func main() { fmt.Println("First 100 brilliant numbers:") brilliant := getBrilliant(2, 10000, false).bc.([]int) sort.Ints(brilliant) brilliant = brilliant[0:100] for i := 0; i < len(brilliant); i++ { fmt.Printf("%4d ", brilliant[i]) if (i+1)%10 == 0 { fmt.Println() } } fmt.Println() for k := 1; k <= 13; k++ { limit := int(math.Pow(10, float64(k))) r := getBrilliant(k, limit, true) total := r.bc.(int) next := r.next climit := rcu.Commatize(limit) ctotal := rcu.Commatize(total + 1) cnext := rcu.Commatize(next) fmt.Printf("First >= %18s is %14s in the series: %18s\n", climit, ctotal, cnext) } }
import java.util.*; public class BrilliantNumbers { public static void main(String[] args) { var primesByDigits = getPrimesByDigits(100000000); System.out.println("First 100 brilliant numbers:"); List<Integer> brilliantNumbers = new ArrayList<>(); for (var primes : primesByDigits) { int n = primes.size(); for (int i = 0; i < n; ++i) { int prime1 = primes.get(i); for (int j = i; j < n; ++j) { int prime2 = primes.get(j); brilliantNumbers.add(prime1 * prime2); } } if (brilliantNumbers.size() >= 100) break; } Collections.sort(brilliantNumbers); for (int i = 0; i < 100; ++i) { char c = (i + 1) % 10 == 0 ? '\n' : ' '; System.out.printf("%,5d%c", brilliantNumbers.get(i), c); } System.out.println(); long power = 10; long count = 0; for (int p = 1; p < 2 * primesByDigits.size(); ++p) { var primes = primesByDigits.get(p / 2); long position = count + 1; long minProduct = 0; int n = primes.size(); for (int i = 0; i < n; ++i) { long prime1 = primes.get(i); var primes2 = primes.subList(i, n); int q = (int)((power + prime1 - 1) / prime1); int j = Collections.binarySearch(primes2, q); if (j == n) continue; if (j < 0) j = -(j + 1); long prime2 = primes2.get(j); long product = prime1 * prime2; if (minProduct == 0 || product < minProduct) minProduct = product; position += j; if (prime1 >= prime2) break; } System.out.printf("First brilliant number >= 10^%d is %,d at position %,d\n", p, minProduct, position); power *= 10; if (p % 2 == 1) { long size = primes.size(); count += size * (size + 1) / 2; } } } private static List<List<Integer>> getPrimesByDigits(int limit) { PrimeGenerator primeGen = new PrimeGenerator(100000, 100000); List<List<Integer>> primesByDigits = new ArrayList<>(); List<Integer> primes = new ArrayList<>(); for (int p = 10; p <= limit; ) { int prime = primeGen.nextPrime(); if (prime > p) { primesByDigits.add(primes); primes = new ArrayList<>(); p *= 10; } primes.add(prime); } return primesByDigits; } }
Port the provided Go code into Java while preserving the original functionality.
package main import ( "fmt" "math" "rcu" "sort" ) var primes = rcu.Primes(1e8 - 1) type res struct { bc interface{} next int } func getBrilliant(digits, limit int, countOnly bool) res { var brilliant []int count := 0 pow := 1 next := math.MaxInt for k := 1; k <= digits; k++ { var s []int for _, p := range primes { if p >= pow*10 { break } if p > pow { s = append(s, p) } } for i := 0; i < len(s); i++ { for j := i; j < len(s); j++ { prod := s[i] * s[j] if prod < limit { if countOnly { count++ } else { brilliant = append(brilliant, prod) } } else { if next > prod { next = prod } break } } } pow *= 10 } if countOnly { return res{count, next} } return res{brilliant, next} } func main() { fmt.Println("First 100 brilliant numbers:") brilliant := getBrilliant(2, 10000, false).bc.([]int) sort.Ints(brilliant) brilliant = brilliant[0:100] for i := 0; i < len(brilliant); i++ { fmt.Printf("%4d ", brilliant[i]) if (i+1)%10 == 0 { fmt.Println() } } fmt.Println() for k := 1; k <= 13; k++ { limit := int(math.Pow(10, float64(k))) r := getBrilliant(k, limit, true) total := r.bc.(int) next := r.next climit := rcu.Commatize(limit) ctotal := rcu.Commatize(total + 1) cnext := rcu.Commatize(next) fmt.Printf("First >= %18s is %14s in the series: %18s\n", climit, ctotal, cnext) } }
import java.util.*; public class BrilliantNumbers { public static void main(String[] args) { var primesByDigits = getPrimesByDigits(100000000); System.out.println("First 100 brilliant numbers:"); List<Integer> brilliantNumbers = new ArrayList<>(); for (var primes : primesByDigits) { int n = primes.size(); for (int i = 0; i < n; ++i) { int prime1 = primes.get(i); for (int j = i; j < n; ++j) { int prime2 = primes.get(j); brilliantNumbers.add(prime1 * prime2); } } if (brilliantNumbers.size() >= 100) break; } Collections.sort(brilliantNumbers); for (int i = 0; i < 100; ++i) { char c = (i + 1) % 10 == 0 ? '\n' : ' '; System.out.printf("%,5d%c", brilliantNumbers.get(i), c); } System.out.println(); long power = 10; long count = 0; for (int p = 1; p < 2 * primesByDigits.size(); ++p) { var primes = primesByDigits.get(p / 2); long position = count + 1; long minProduct = 0; int n = primes.size(); for (int i = 0; i < n; ++i) { long prime1 = primes.get(i); var primes2 = primes.subList(i, n); int q = (int)((power + prime1 - 1) / prime1); int j = Collections.binarySearch(primes2, q); if (j == n) continue; if (j < 0) j = -(j + 1); long prime2 = primes2.get(j); long product = prime1 * prime2; if (minProduct == 0 || product < minProduct) minProduct = product; position += j; if (prime1 >= prime2) break; } System.out.printf("First brilliant number >= 10^%d is %,d at position %,d\n", p, minProduct, position); power *= 10; if (p % 2 == 1) { long size = primes.size(); count += size * (size + 1) / 2; } } } private static List<List<Integer>> getPrimesByDigits(int limit) { PrimeGenerator primeGen = new PrimeGenerator(100000, 100000); List<List<Integer>> primesByDigits = new ArrayList<>(); List<Integer> primes = new ArrayList<>(); for (int p = 10; p <= limit; ) { int prime = primeGen.nextPrime(); if (prime > p) { primesByDigits.add(primes); primes = new ArrayList<>(); p *= 10; } primes.add(prime); } return primesByDigits; } }
Please provide an equivalent version of this Go code in Java.
package main import ( "bytes" "fmt" "io/ioutil" "log" "strings" ) func contains(a []string, s string) bool { for _, e := range a { if e == s { return true } } return false } func oneAway(a, b string) bool { sum := 0 for i := 0; i < len(a); i++ { if a[i] != b[i] { sum++ } } return sum == 1 } func wordLadder(words []string, a, b string) { l := len(a) var poss []string for _, word := range words { if len(word) == l { poss = append(poss, word) } } todo := [][]string{{a}} for len(todo) > 0 { curr := todo[0] todo = todo[1:] var next []string for _, word := range poss { if oneAway(word, curr[len(curr)-1]) { next = append(next, word) } } if contains(next, b) { curr = append(curr, b) fmt.Println(strings.Join(curr, " -> ")) return } for i := len(poss) - 1; i >= 0; i-- { if contains(next, poss[i]) { copy(poss[i:], poss[i+1:]) poss[len(poss)-1] = "" poss = poss[:len(poss)-1] } } for _, s := range next { temp := make([]string, len(curr)) copy(temp, curr) temp = append(temp, s) todo = append(todo, temp) } } fmt.Println(a, "into", b, "cannot be done.") } func main() { b, err := ioutil.ReadFile("unixdict.txt") if err != nil { log.Fatal("Error reading file") } bwords := bytes.Fields(b) words := make([]string, len(bwords)) for i, bword := range bwords { words[i] = string(bword) } pairs := [][]string{ {"boy", "man"}, {"girl", "lady"}, {"john", "jane"}, {"child", "adult"}, } for _, pair := range pairs { wordLadder(words, pair[0], pair[1]) } }
import java.io.IOException; import java.nio.file.Files; import java.nio.file.Path; import java.util.ArrayList; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.PriorityQueue; import java.util.Set; import java.util.stream.IntStream; public class WordLadder { private static int distance(String s1, String s2) { assert s1.length() == s2.length(); return (int) IntStream.range(0, s1.length()) .filter(i -> s1.charAt(i) != s2.charAt(i)) .count(); } private static void wordLadder(Map<Integer, Set<String>> words, String fw, String tw) { wordLadder(words, fw, tw, 8); } private static void wordLadder(Map<Integer, Set<String>> words, String fw, String tw, int limit) { if (fw.length() != tw.length()) { throw new IllegalArgumentException("From word and to word must have the same length"); } Set<String> ws = words.get(fw.length()); if (ws.contains(fw)) { List<String> primeList = new ArrayList<>(); primeList.add(fw); PriorityQueue<List<String>> queue = new PriorityQueue<>((chain1, chain2) -> { int cmp1 = Integer.compare(chain1.size(), chain2.size()); if (cmp1 == 0) { String last1 = chain1.get(chain1.size() - 1); int d1 = distance(last1, tw); String last2 = chain2.get(chain2.size() - 1); int d2 = distance(last2, tw); return Integer.compare(d1, d2); } return cmp1; }); queue.add(primeList); while (queue.size() > 0) { List<String> curr = queue.remove(); if (curr.size() > limit) { continue; } String last = curr.get(curr.size() - 1); for (String word : ws) { if (distance(last, word) == 1) { if (word.equals(tw)) { curr.add(word); System.out.println(String.join(" -> ", curr)); return; } if (!curr.contains(word)) { List<String> cp = new ArrayList<>(curr); cp.add(word); queue.add(cp); } } } } } System.err.printf("Cannot turn `%s` into `%s`%n", fw, tw); } public static void main(String[] args) throws IOException { Map<Integer, Set<String>> words = new HashMap<>(); for (String line : Files.readAllLines(Path.of("unixdict.txt"))) { Set<String> wl = words.computeIfAbsent(line.length(), HashSet::new); wl.add(line); } wordLadder(words, "boy", "man"); wordLadder(words, "girl", "lady"); wordLadder(words, "john", "jane"); wordLadder(words, "child", "adult"); wordLadder(words, "cat", "dog"); wordLadder(words, "lead", "gold"); wordLadder(words, "white", "black"); wordLadder(words, "bubble", "tickle", 12); } }
Translate this program into Java but keep the logic exactly as in Go.
package main import ( "bytes" "fmt" "io/ioutil" "log" "strings" ) func contains(a []string, s string) bool { for _, e := range a { if e == s { return true } } return false } func oneAway(a, b string) bool { sum := 0 for i := 0; i < len(a); i++ { if a[i] != b[i] { sum++ } } return sum == 1 } func wordLadder(words []string, a, b string) { l := len(a) var poss []string for _, word := range words { if len(word) == l { poss = append(poss, word) } } todo := [][]string{{a}} for len(todo) > 0 { curr := todo[0] todo = todo[1:] var next []string for _, word := range poss { if oneAway(word, curr[len(curr)-1]) { next = append(next, word) } } if contains(next, b) { curr = append(curr, b) fmt.Println(strings.Join(curr, " -> ")) return } for i := len(poss) - 1; i >= 0; i-- { if contains(next, poss[i]) { copy(poss[i:], poss[i+1:]) poss[len(poss)-1] = "" poss = poss[:len(poss)-1] } } for _, s := range next { temp := make([]string, len(curr)) copy(temp, curr) temp = append(temp, s) todo = append(todo, temp) } } fmt.Println(a, "into", b, "cannot be done.") } func main() { b, err := ioutil.ReadFile("unixdict.txt") if err != nil { log.Fatal("Error reading file") } bwords := bytes.Fields(b) words := make([]string, len(bwords)) for i, bword := range bwords { words[i] = string(bword) } pairs := [][]string{ {"boy", "man"}, {"girl", "lady"}, {"john", "jane"}, {"child", "adult"}, } for _, pair := range pairs { wordLadder(words, pair[0], pair[1]) } }
import java.io.IOException; import java.nio.file.Files; import java.nio.file.Path; import java.util.ArrayList; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.PriorityQueue; import java.util.Set; import java.util.stream.IntStream; public class WordLadder { private static int distance(String s1, String s2) { assert s1.length() == s2.length(); return (int) IntStream.range(0, s1.length()) .filter(i -> s1.charAt(i) != s2.charAt(i)) .count(); } private static void wordLadder(Map<Integer, Set<String>> words, String fw, String tw) { wordLadder(words, fw, tw, 8); } private static void wordLadder(Map<Integer, Set<String>> words, String fw, String tw, int limit) { if (fw.length() != tw.length()) { throw new IllegalArgumentException("From word and to word must have the same length"); } Set<String> ws = words.get(fw.length()); if (ws.contains(fw)) { List<String> primeList = new ArrayList<>(); primeList.add(fw); PriorityQueue<List<String>> queue = new PriorityQueue<>((chain1, chain2) -> { int cmp1 = Integer.compare(chain1.size(), chain2.size()); if (cmp1 == 0) { String last1 = chain1.get(chain1.size() - 1); int d1 = distance(last1, tw); String last2 = chain2.get(chain2.size() - 1); int d2 = distance(last2, tw); return Integer.compare(d1, d2); } return cmp1; }); queue.add(primeList); while (queue.size() > 0) { List<String> curr = queue.remove(); if (curr.size() > limit) { continue; } String last = curr.get(curr.size() - 1); for (String word : ws) { if (distance(last, word) == 1) { if (word.equals(tw)) { curr.add(word); System.out.println(String.join(" -> ", curr)); return; } if (!curr.contains(word)) { List<String> cp = new ArrayList<>(curr); cp.add(word); queue.add(cp); } } } } } System.err.printf("Cannot turn `%s` into `%s`%n", fw, tw); } public static void main(String[] args) throws IOException { Map<Integer, Set<String>> words = new HashMap<>(); for (String line : Files.readAllLines(Path.of("unixdict.txt"))) { Set<String> wl = words.computeIfAbsent(line.length(), HashSet::new); wl.add(line); } wordLadder(words, "boy", "man"); wordLadder(words, "girl", "lady"); wordLadder(words, "john", "jane"); wordLadder(words, "child", "adult"); wordLadder(words, "cat", "dog"); wordLadder(words, "lead", "gold"); wordLadder(words, "white", "black"); wordLadder(words, "bubble", "tickle", 12); } }
Write a version of this Go function in Java with identical behavior.
package main import ( "fmt" "rcu" ) func main() { limit := int(1e9) gapStarts := make(map[int]int) primes := rcu.Primes(limit * 5) for i := 1; i < len(primes); i++ { gap := primes[i] - primes[i-1] if _, ok := gapStarts[gap]; !ok { gapStarts[gap] = primes[i-1] } } pm := 10 gap1 := 2 for { for _, ok := gapStarts[gap1]; !ok; { gap1 += 2 } start1 := gapStarts[gap1] gap2 := gap1 + 2 if _, ok := gapStarts[gap2]; !ok { gap1 = gap2 + 2 continue } start2 := gapStarts[gap2] diff := start2 - start1 if diff < 0 { diff = -diff } if diff > pm { cpm := rcu.Commatize(pm) cst1 := rcu.Commatize(start1) cst2 := rcu.Commatize(start2) cd := rcu.Commatize(diff) fmt.Printf("Earliest difference > %s between adjacent prime gap starting primes:\n", cpm) fmt.Printf("Gap %d starts at %s, gap %d starts at %s, difference is %s.\n\n", gap1, cst1, gap2, cst2, cd) if pm == limit { break } pm *= 10 } else { gap1 = gap2 } } }
import java.util.HashMap; import java.util.Map; public class PrimeGaps { private Map<Integer, Integer> gapStarts = new HashMap<>(); private int lastPrime; private PrimeGenerator primeGenerator = new PrimeGenerator(1000, 500000); public static void main(String[] args) { final int limit = 100000000; PrimeGaps pg = new PrimeGaps(); for (int pm = 10, gap1 = 2;;) { int start1 = pg.findGapStart(gap1); int gap2 = gap1 + 2; int start2 = pg.findGapStart(gap2); int diff = start2 > start1 ? start2 - start1 : start1 - start2; if (diff > pm) { System.out.printf( "Earliest difference > %,d between adjacent prime gap starting primes:\n" + "Gap %,d starts at %,d, gap %,d starts at %,d, difference is %,d.\n\n", pm, gap1, start1, gap2, start2, diff); if (pm == limit) break; pm *= 10; } else { gap1 = gap2; } } } private int findGapStart(int gap) { Integer start = gapStarts.get(gap); if (start != null) return start; for (;;) { int prev = lastPrime; lastPrime = primeGenerator.nextPrime(); int diff = lastPrime - prev; gapStarts.putIfAbsent(diff, prev); if (diff == gap) return prev; } } }
Change the following Go code into Java without altering its purpose.
package main import ( "fmt" "rcu" ) func main() { limit := int(1e9) gapStarts := make(map[int]int) primes := rcu.Primes(limit * 5) for i := 1; i < len(primes); i++ { gap := primes[i] - primes[i-1] if _, ok := gapStarts[gap]; !ok { gapStarts[gap] = primes[i-1] } } pm := 10 gap1 := 2 for { for _, ok := gapStarts[gap1]; !ok; { gap1 += 2 } start1 := gapStarts[gap1] gap2 := gap1 + 2 if _, ok := gapStarts[gap2]; !ok { gap1 = gap2 + 2 continue } start2 := gapStarts[gap2] diff := start2 - start1 if diff < 0 { diff = -diff } if diff > pm { cpm := rcu.Commatize(pm) cst1 := rcu.Commatize(start1) cst2 := rcu.Commatize(start2) cd := rcu.Commatize(diff) fmt.Printf("Earliest difference > %s between adjacent prime gap starting primes:\n", cpm) fmt.Printf("Gap %d starts at %s, gap %d starts at %s, difference is %s.\n\n", gap1, cst1, gap2, cst2, cd) if pm == limit { break } pm *= 10 } else { gap1 = gap2 } } }
import java.util.HashMap; import java.util.Map; public class PrimeGaps { private Map<Integer, Integer> gapStarts = new HashMap<>(); private int lastPrime; private PrimeGenerator primeGenerator = new PrimeGenerator(1000, 500000); public static void main(String[] args) { final int limit = 100000000; PrimeGaps pg = new PrimeGaps(); for (int pm = 10, gap1 = 2;;) { int start1 = pg.findGapStart(gap1); int gap2 = gap1 + 2; int start2 = pg.findGapStart(gap2); int diff = start2 > start1 ? start2 - start1 : start1 - start2; if (diff > pm) { System.out.printf( "Earliest difference > %,d between adjacent prime gap starting primes:\n" + "Gap %,d starts at %,d, gap %,d starts at %,d, difference is %,d.\n\n", pm, gap1, start1, gap2, start2, diff); if (pm == limit) break; pm *= 10; } else { gap1 = gap2; } } } private int findGapStart(int gap) { Integer start = gapStarts.get(gap); if (start != null) return start; for (;;) { int prev = lastPrime; lastPrime = primeGenerator.nextPrime(); int diff = lastPrime - prev; gapStarts.putIfAbsent(diff, prev); if (diff == gap) return prev; } } }
Translate the given Go code snippet into Java without altering its behavior.
package main import ( "fmt" "sort" ) type matrix [][]int func dList(n, start int) (r matrix) { start-- a := make([]int, n) for i := range a { a[i] = i } a[0], a[start] = start, a[0] sort.Ints(a[1:]) first := a[1] var recurse func(last int) recurse = func(last int) { if last == first { for j, v := range a[1:] { if j+1 == v { return } } b := make([]int, n) copy(b, a) for i := range b { b[i]++ } r = append(r, b) return } for i := last; i >= 1; i-- { a[i], a[last] = a[last], a[i] recurse(last - 1) a[i], a[last] = a[last], a[i] } } recurse(n - 1) return } func reducedLatinSquare(n int, echo bool) uint64 { if n <= 0 { if echo { fmt.Println("[]\n") } return 0 } else if n == 1 { if echo { fmt.Println("[1]\n") } return 1 } rlatin := make(matrix, n) for i := 0; i < n; i++ { rlatin[i] = make([]int, n) } for j := 0; j < n; j++ { rlatin[0][j] = j + 1 } count := uint64(0) var recurse func(i int) recurse = func(i int) { rows := dList(n, i) outer: for r := 0; r < len(rows); r++ { copy(rlatin[i-1], rows[r]) for k := 0; k < i-1; k++ { for j := 1; j < n; j++ { if rlatin[k][j] == rlatin[i-1][j] { if r < len(rows)-1 { continue outer } else if i > 2 { return } } } } if i < n { recurse(i + 1) } else { count++ if echo { printSquare(rlatin, n) } } } return } recurse(2) return count } func printSquare(latin matrix, n int) { for i := 0; i < n; i++ { fmt.Println(latin[i]) } fmt.Println() } func factorial(n uint64) uint64 { if n == 0 { return 1 } prod := uint64(1) for i := uint64(2); i <= n; i++ { prod *= i } return prod } func main() { fmt.Println("The four reduced latin squares of order 4 are:\n") reducedLatinSquare(4, true) fmt.Println("The size of the set of reduced latin squares for the following orders") fmt.Println("and hence the total number of latin squares of these orders are:\n") for n := uint64(1); n <= 6; n++ { size := reducedLatinSquare(int(n), false) f := factorial(n - 1) f *= f * n * size fmt.Printf("Order %d: Size %-4d x %d! x %d! => Total %d\n", n, size, n, n-1, f) } }
import java.math.BigInteger; import java.util.ArrayList; import java.util.Arrays; import java.util.List; public class LatinSquaresInReducedForm { public static void main(String[] args) { System.out.printf("Reduced latin squares of order 4:%n"); for ( LatinSquare square : getReducedLatinSquares(4) ) { System.out.printf("%s%n", square); } System.out.printf("Compute the number of latin squares from count of reduced latin squares:%n(Reduced Latin Square Count) * n! * (n-1)! = Latin Square Count%n"); for ( int n = 1 ; n <= 6 ; n++ ) { List<LatinSquare> list = getReducedLatinSquares(n); System.out.printf("Size = %d, %d * %d * %d = %,d%n", n, list.size(), fact(n), fact(n-1), list.size()*fact(n)*fact(n-1)); } } private static long fact(int n) { if ( n == 0 ) { return 1; } int prod = 1; for ( int i = 1 ; i <= n ; i++ ) { prod *= i; } return prod; } private static List<LatinSquare> getReducedLatinSquares(int n) { List<LatinSquare> squares = new ArrayList<>(); squares.add(new LatinSquare(n)); PermutationGenerator permGen = new PermutationGenerator(n); for ( int fillRow = 1 ; fillRow < n ; fillRow++ ) { List<LatinSquare> squaresNext = new ArrayList<>(); for ( LatinSquare square : squares ) { while ( permGen.hasMore() ) { int[] perm = permGen.getNext(); if ( (perm[0]+1) != (fillRow+1) ) { continue; } boolean permOk = true; done: for ( int row = 0 ; row < fillRow ; row++ ) { for ( int col = 0 ; col < n ; col++ ) { if ( square.get(row, col) == (perm[col]+1) ) { permOk = false; break done; } } } if ( permOk ) { LatinSquare newSquare = new LatinSquare(square); for ( int col = 0 ; col < n ; col++ ) { newSquare.set(fillRow, col, perm[col]+1); } squaresNext.add(newSquare); } } permGen.reset(); } squares = squaresNext; } return squares; } @SuppressWarnings("unused") private static int[] display(int[] in) { int [] out = new int[in.length]; for ( int i = 0 ; i < in.length ; i++ ) { out[i] = in[i] + 1; } return out; } private static class LatinSquare { int[][] square; int size; public LatinSquare(int n) { square = new int[n][n]; size = n; for ( int col = 0 ; col < n ; col++ ) { set(0, col, col + 1); } } public LatinSquare(LatinSquare ls) { int n = ls.size; square = new int[n][n]; size = n; for ( int row = 0 ; row < n ; row++ ) { for ( int col = 0 ; col < n ; col++ ) { set(row, col, ls.get(row, col)); } } } public void set(int row, int col, int value) { square[row][col] = value; } public int get(int row, int col) { return square[row][col]; } @Override public String toString() { StringBuilder sb = new StringBuilder(); for ( int row = 0 ; row < size ; row++ ) { sb.append(Arrays.toString(square[row])); sb.append("\n"); } return sb.toString(); } } private static class PermutationGenerator { private int[] a; private BigInteger numLeft; private BigInteger total; public PermutationGenerator (int n) { if (n < 1) { throw new IllegalArgumentException ("Min 1"); } a = new int[n]; total = getFactorial(n); reset(); } private void reset () { for ( int i = 0 ; i < a.length ; i++ ) { a[i] = i; } numLeft = new BigInteger(total.toString()); } public boolean hasMore() { return numLeft.compareTo(BigInteger.ZERO) == 1; } private static BigInteger getFactorial (int n) { BigInteger fact = BigInteger.ONE; for ( int i = n ; i > 1 ; i-- ) { fact = fact.multiply(new BigInteger(Integer.toString(i))); } return fact; } public int[] getNext() { if ( numLeft.equals(total) ) { numLeft = numLeft.subtract (BigInteger.ONE); return a; } int j = a.length - 2; while ( a[j] > a[j+1] ) { j--; } int k = a.length - 1; while ( a[j] > a[k] ) { k--; } int temp = a[k]; a[k] = a[j]; a[j] = temp; int r = a.length - 1; int s = j + 1; while (r > s) { int temp2 = a[s]; a[s] = a[r]; a[r] = temp2; r--; s++; } numLeft = numLeft.subtract(BigInteger.ONE); return a; } } }
Write the same code in Java as shown below in Go.
package main import ( "fmt" "regexp" ) var bits = []string{ "0 0 0 1 1 0 1 ", "0 0 1 1 0 0 1 ", "0 0 1 0 0 1 1 ", "0 1 1 1 1 0 1 ", "0 1 0 0 0 1 1 ", "0 1 1 0 0 0 1 ", "0 1 0 1 1 1 1 ", "0 1 1 1 0 1 1 ", "0 1 1 0 1 1 1 ", "0 0 0 1 0 1 1 ", } var ( lhs = make(map[string]int) rhs = make(map[string]int) ) var weights = []int{3, 1, 3, 1, 3, 1, 3, 1, 3, 1, 3, 1} const ( s = "# #" m = " # # " e = "# #" d = "(?:#| ){7}" ) func init() { for i := 0; i <= 9; i++ { lt := make([]byte, 7) rt := make([]byte, 7) for j := 0; j < 14; j += 2 { if bits[i][j] == '1' { lt[j/2] = '#' rt[j/2] = ' ' } else { lt[j/2] = ' ' rt[j/2] = '#' } } lhs[string(lt)] = i rhs[string(rt)] = i } } func reverse(s string) string { b := []byte(s) for i, j := 0, len(b)-1; i < j; i, j = i+1, j-1 { b[i], b[j] = b[j], b[i] } return string(b) } func main() { barcodes := []string{ " # # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # # ", " # # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # # ", " # # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # # ", " # # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # # ", " # # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # # ", " # # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # # ", " # # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # # ", " # # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # # ", " # # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # # ", " # # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # # ", } expr := fmt.Sprintf(`^\s*%s(%s)(%s)(%s)(%s)(%s)(%s)%s(%s)(%s)(%s)(%s)(%s)(%s)%s\s*$`, s, d, d, d, d, d, d, m, d, d, d, d, d, d, e) rx := regexp.MustCompile(expr) fmt.Println("UPC-A barcodes:") for i, bc := range barcodes { for j := 0; j <= 1; j++ { if !rx.MatchString(bc) { fmt.Printf("%2d: Invalid format\n", i+1) break } codes := rx.FindStringSubmatch(bc) digits := make([]int, 12) var invalid, ok bool for i := 1; i <= 6; i++ { digits[i-1], ok = lhs[codes[i]] if !ok { invalid = true } digits[i+5], ok = rhs[codes[i+6]] if !ok { invalid = true } } if invalid { if j == 0 { bc = reverse(bc) continue } else { fmt.Printf("%2d: Invalid digit(s)\n", i+1) break } } sum := 0 for i, d := range digits { sum += weights[i] * d } if sum%10 != 0 { fmt.Printf("%2d: Checksum error\n", i+1) break } else { ud := "" if j == 1 { ud = "(upside down)" } fmt.Printf("%2d: %v %s\n", i+1, digits, ud) break } } } }
import java.util.ArrayList; import java.util.List; import java.util.Map; import java.util.function.Consumer; import java.util.function.Function; import java.util.stream.Collectors; public class UPC { private static final int SEVEN = 7; private static final Map<String, Integer> LEFT_DIGITS = Map.of( " ## #", 0, " ## #", 1, " # ##", 2, " #### #", 3, " # ##", 4, " ## #", 5, " # ####", 6, " ### ##", 7, " ## ###", 8, " # ##", 9 ); private static final Map<String, Integer> RIGHT_DIGITS = LEFT_DIGITS.entrySet() .stream() .collect(Collectors.toMap( entry -> entry.getKey() .replace(' ', 's') .replace('#', ' ') .replace('s', '#'), Map.Entry::getValue )); private static final String END_SENTINEL = "# #"; private static final String MID_SENTINEL = " # # "; private static void decodeUPC(String input) { Function<String, Map.Entry<Boolean, List<Integer>>> decode = (String candidate) -> { int pos = 0; var part = candidate.substring(pos, pos + END_SENTINEL.length()); List<Integer> output = new ArrayList<>(); if (END_SENTINEL.equals(part)) { pos += END_SENTINEL.length(); } else { return Map.entry(false, output); } for (int i = 1; i < SEVEN; i++) { part = candidate.substring(pos, pos + SEVEN); pos += SEVEN; if (LEFT_DIGITS.containsKey(part)) { output.add(LEFT_DIGITS.get(part)); } else { return Map.entry(false, output); } } part = candidate.substring(pos, pos + MID_SENTINEL.length()); if (MID_SENTINEL.equals(part)) { pos += MID_SENTINEL.length(); } else { return Map.entry(false, output); } for (int i = 1; i < SEVEN; i++) { part = candidate.substring(pos, pos + SEVEN); pos += SEVEN; if (RIGHT_DIGITS.containsKey(part)) { output.add(RIGHT_DIGITS.get(part)); } else { return Map.entry(false, output); } } part = candidate.substring(pos, pos + END_SENTINEL.length()); if (!END_SENTINEL.equals(part)) { return Map.entry(false, output); } int sum = 0; for (int i = 0; i < output.size(); i++) { if (i % 2 == 0) { sum += 3 * output.get(i); } else { sum += output.get(i); } } return Map.entry(sum % 10 == 0, output); }; Consumer<List<Integer>> printList = list -> { var it = list.iterator(); System.out.print('['); if (it.hasNext()) { System.out.print(it.next()); } while (it.hasNext()) { System.out.print(", "); System.out.print(it.next()); } System.out.print(']'); }; var candidate = input.trim(); var out = decode.apply(candidate); if (out.getKey()) { printList.accept(out.getValue()); System.out.println(); } else { StringBuilder builder = new StringBuilder(candidate); builder.reverse(); out = decode.apply(builder.toString()); if (out.getKey()) { printList.accept(out.getValue()); System.out.println(" Upside down"); } else if (out.getValue().size() == 12) { System.out.println("Invalid checksum"); } else { System.out.println("Invalid digit(s)"); } } } public static void main(String[] args) { var barcodes = List.of( " # # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # # ", " # # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # # ", " # # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # # ", " # # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # # ", " # # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # # ", " # # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # # ", " # # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # # ", " # # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # # ", " # # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # # ", " # # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # # " ); barcodes.forEach(UPC::decodeUPC); } }
Convert this Go block to Java, preserving its control flow and logic.
package main import ( "fmt" "regexp" ) var bits = []string{ "0 0 0 1 1 0 1 ", "0 0 1 1 0 0 1 ", "0 0 1 0 0 1 1 ", "0 1 1 1 1 0 1 ", "0 1 0 0 0 1 1 ", "0 1 1 0 0 0 1 ", "0 1 0 1 1 1 1 ", "0 1 1 1 0 1 1 ", "0 1 1 0 1 1 1 ", "0 0 0 1 0 1 1 ", } var ( lhs = make(map[string]int) rhs = make(map[string]int) ) var weights = []int{3, 1, 3, 1, 3, 1, 3, 1, 3, 1, 3, 1} const ( s = "# #" m = " # # " e = "# #" d = "(?:#| ){7}" ) func init() { for i := 0; i <= 9; i++ { lt := make([]byte, 7) rt := make([]byte, 7) for j := 0; j < 14; j += 2 { if bits[i][j] == '1' { lt[j/2] = '#' rt[j/2] = ' ' } else { lt[j/2] = ' ' rt[j/2] = '#' } } lhs[string(lt)] = i rhs[string(rt)] = i } } func reverse(s string) string { b := []byte(s) for i, j := 0, len(b)-1; i < j; i, j = i+1, j-1 { b[i], b[j] = b[j], b[i] } return string(b) } func main() { barcodes := []string{ " # # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # # ", " # # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # # ", " # # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # # ", " # # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # # ", " # # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # # ", " # # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # # ", " # # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # # ", " # # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # # ", " # # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # # ", " # # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # # ", } expr := fmt.Sprintf(`^\s*%s(%s)(%s)(%s)(%s)(%s)(%s)%s(%s)(%s)(%s)(%s)(%s)(%s)%s\s*$`, s, d, d, d, d, d, d, m, d, d, d, d, d, d, e) rx := regexp.MustCompile(expr) fmt.Println("UPC-A barcodes:") for i, bc := range barcodes { for j := 0; j <= 1; j++ { if !rx.MatchString(bc) { fmt.Printf("%2d: Invalid format\n", i+1) break } codes := rx.FindStringSubmatch(bc) digits := make([]int, 12) var invalid, ok bool for i := 1; i <= 6; i++ { digits[i-1], ok = lhs[codes[i]] if !ok { invalid = true } digits[i+5], ok = rhs[codes[i+6]] if !ok { invalid = true } } if invalid { if j == 0 { bc = reverse(bc) continue } else { fmt.Printf("%2d: Invalid digit(s)\n", i+1) break } } sum := 0 for i, d := range digits { sum += weights[i] * d } if sum%10 != 0 { fmt.Printf("%2d: Checksum error\n", i+1) break } else { ud := "" if j == 1 { ud = "(upside down)" } fmt.Printf("%2d: %v %s\n", i+1, digits, ud) break } } } }
import java.util.ArrayList; import java.util.List; import java.util.Map; import java.util.function.Consumer; import java.util.function.Function; import java.util.stream.Collectors; public class UPC { private static final int SEVEN = 7; private static final Map<String, Integer> LEFT_DIGITS = Map.of( " ## #", 0, " ## #", 1, " # ##", 2, " #### #", 3, " # ##", 4, " ## #", 5, " # ####", 6, " ### ##", 7, " ## ###", 8, " # ##", 9 ); private static final Map<String, Integer> RIGHT_DIGITS = LEFT_DIGITS.entrySet() .stream() .collect(Collectors.toMap( entry -> entry.getKey() .replace(' ', 's') .replace('#', ' ') .replace('s', '#'), Map.Entry::getValue )); private static final String END_SENTINEL = "# #"; private static final String MID_SENTINEL = " # # "; private static void decodeUPC(String input) { Function<String, Map.Entry<Boolean, List<Integer>>> decode = (String candidate) -> { int pos = 0; var part = candidate.substring(pos, pos + END_SENTINEL.length()); List<Integer> output = new ArrayList<>(); if (END_SENTINEL.equals(part)) { pos += END_SENTINEL.length(); } else { return Map.entry(false, output); } for (int i = 1; i < SEVEN; i++) { part = candidate.substring(pos, pos + SEVEN); pos += SEVEN; if (LEFT_DIGITS.containsKey(part)) { output.add(LEFT_DIGITS.get(part)); } else { return Map.entry(false, output); } } part = candidate.substring(pos, pos + MID_SENTINEL.length()); if (MID_SENTINEL.equals(part)) { pos += MID_SENTINEL.length(); } else { return Map.entry(false, output); } for (int i = 1; i < SEVEN; i++) { part = candidate.substring(pos, pos + SEVEN); pos += SEVEN; if (RIGHT_DIGITS.containsKey(part)) { output.add(RIGHT_DIGITS.get(part)); } else { return Map.entry(false, output); } } part = candidate.substring(pos, pos + END_SENTINEL.length()); if (!END_SENTINEL.equals(part)) { return Map.entry(false, output); } int sum = 0; for (int i = 0; i < output.size(); i++) { if (i % 2 == 0) { sum += 3 * output.get(i); } else { sum += output.get(i); } } return Map.entry(sum % 10 == 0, output); }; Consumer<List<Integer>> printList = list -> { var it = list.iterator(); System.out.print('['); if (it.hasNext()) { System.out.print(it.next()); } while (it.hasNext()) { System.out.print(", "); System.out.print(it.next()); } System.out.print(']'); }; var candidate = input.trim(); var out = decode.apply(candidate); if (out.getKey()) { printList.accept(out.getValue()); System.out.println(); } else { StringBuilder builder = new StringBuilder(candidate); builder.reverse(); out = decode.apply(builder.toString()); if (out.getKey()) { printList.accept(out.getValue()); System.out.println(" Upside down"); } else if (out.getValue().size() == 12) { System.out.println("Invalid checksum"); } else { System.out.println("Invalid digit(s)"); } } } public static void main(String[] args) { var barcodes = List.of( " # # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # # ", " # # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # # ", " # # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # # ", " # # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # # ", " # # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # # ", " # # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # # ", " # # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # # ", " # # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # # ", " # # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # # ", " # # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # # " ); barcodes.forEach(UPC::decodeUPC); } }
Convert the following code from Go to Java, ensuring the logic remains intact.
package main import ( "bufio" "fmt" "os" "strings" ) type playfairOption int const ( noQ playfairOption = iota iEqualsJ ) type playfair struct { keyword string pfo playfairOption table [5][5]byte } func (p *playfair) init() { var used [26]bool if p.pfo == noQ { used[16] = true } else { used[9] = true } alphabet := strings.ToUpper(p.keyword) + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" for i, j, k := 0, 0, 0; k < len(alphabet); k++ { c := alphabet[k] if c < 'A' || c > 'Z' { continue } d := int(c - 65) if !used[d] { p.table[i][j] = c used[d] = true j++ if j == 5 { i++ if i == 5 { break } j = 0 } } } } func (p *playfair) getCleanText(plainText string) string { plainText = strings.ToUpper(plainText) var cleanText strings.Builder prevByte := byte('\000') for i := 0; i < len(plainText); i++ { nextByte := plainText[i] if nextByte < 'A' || nextByte > 'Z' || (nextByte == 'Q' && p.pfo == noQ) { continue } if nextByte == 'J' && p.pfo == iEqualsJ { nextByte = 'I' } if nextByte != prevByte { cleanText.WriteByte(nextByte) } else { cleanText.WriteByte('X') cleanText.WriteByte(nextByte) } prevByte = nextByte } l := cleanText.Len() if l%2 == 1 { if cleanText.String()[l-1] != 'X' { cleanText.WriteByte('X') } else { cleanText.WriteByte('Z') } } return cleanText.String() } func (p *playfair) findByte(c byte) (int, int) { for i := 0; i < 5; i++ { for j := 0; j < 5; j++ { if p.table[i][j] == c { return i, j } } } return -1, -1 } func (p *playfair) encode(plainText string) string { cleanText := p.getCleanText(plainText) var cipherText strings.Builder l := len(cleanText) for i := 0; i < l; i += 2 { row1, col1 := p.findByte(cleanText[i]) row2, col2 := p.findByte(cleanText[i+1]) switch { case row1 == row2: cipherText.WriteByte(p.table[row1][(col1+1)%5]) cipherText.WriteByte(p.table[row2][(col2+1)%5]) case col1 == col2: cipherText.WriteByte(p.table[(row1+1)%5][col1]) cipherText.WriteByte(p.table[(row2+1)%5][col2]) default: cipherText.WriteByte(p.table[row1][col2]) cipherText.WriteByte(p.table[row2][col1]) } if i < l-1 { cipherText.WriteByte(' ') } } return cipherText.String() } func (p *playfair) decode(cipherText string) string { var decodedText strings.Builder l := len(cipherText) for i := 0; i < l; i += 3 { row1, col1 := p.findByte(cipherText[i]) row2, col2 := p.findByte(cipherText[i+1]) switch { case row1 == row2: temp := 4 if col1 > 0 { temp = col1 - 1 } decodedText.WriteByte(p.table[row1][temp]) temp = 4 if col2 > 0 { temp = col2 - 1 } decodedText.WriteByte(p.table[row2][temp]) case col1 == col2: temp := 4 if row1 > 0 { temp = row1 - 1 } decodedText.WriteByte(p.table[temp][col1]) temp = 4 if row2 > 0 { temp = row2 - 1 } decodedText.WriteByte(p.table[temp][col2]) default: decodedText.WriteByte(p.table[row1][col2]) decodedText.WriteByte(p.table[row2][col1]) } if i < l-1 { decodedText.WriteByte(' ') } } return decodedText.String() } func (p *playfair) printTable() { fmt.Println("The table to be used is :\n") for i := 0; i < 5; i++ { for j := 0; j < 5; j++ { fmt.Printf("%c ", p.table[i][j]) } fmt.Println() } } func main() { scanner := bufio.NewScanner(os.Stdin) fmt.Print("Enter Playfair keyword : ") scanner.Scan() keyword := scanner.Text() var ignoreQ string for ignoreQ != "y" && ignoreQ != "n" { fmt.Print("Ignore Q when building table y/n : ") scanner.Scan() ignoreQ = strings.ToLower(scanner.Text()) } pfo := noQ if ignoreQ == "n" { pfo = iEqualsJ } var table [5][5]byte pf := &playfair{keyword, pfo, table} pf.init() pf.printTable() fmt.Print("\nEnter plain text : ") scanner.Scan() plainText := scanner.Text() if err := scanner.Err(); err != nil { fmt.Fprintln(os.Stderr, "reading standard input:", err) return } encodedText := pf.encode(plainText) fmt.Println("\nEncoded text is :", encodedText) decodedText := pf.decode(encodedText) fmt.Println("Deccoded text is :", decodedText) }
import java.awt.Point; import java.util.Scanner; public class PlayfairCipher { private static char[][] charTable; private static Point[] positions; public static void main(String[] args) { Scanner sc = new Scanner(System.in); String key = prompt("Enter an encryption key (min length 6): ", sc, 6); String txt = prompt("Enter the message: ", sc, 1); String jti = prompt("Replace J with I? y/n: ", sc, 1); boolean changeJtoI = jti.equalsIgnoreCase("y"); createTable(key, changeJtoI); String enc = encode(prepareText(txt, changeJtoI)); System.out.printf("%nEncoded message: %n%s%n", enc); System.out.printf("%nDecoded message: %n%s%n", decode(enc)); } private static String prompt(String promptText, Scanner sc, int minLen) { String s; do { System.out.print(promptText); s = sc.nextLine().trim(); } while (s.length() < minLen); return s; } private static String prepareText(String s, boolean changeJtoI) { s = s.toUpperCase().replaceAll("[^A-Z]", ""); return changeJtoI ? s.replace("J", "I") : s.replace("Q", ""); } private static void createTable(String key, boolean changeJtoI) { charTable = new char[5][5]; positions = new Point[26]; String s = prepareText(key + "ABCDEFGHIJKLMNOPQRSTUVWXYZ", changeJtoI); int len = s.length(); for (int i = 0, k = 0; i < len; i++) { char c = s.charAt(i); if (positions[c - 'A'] == null) { charTable[k / 5][k % 5] = c; positions[c - 'A'] = new Point(k % 5, k / 5); k++; } } } private static String encode(String s) { StringBuilder sb = new StringBuilder(s); for (int i = 0; i < sb.length(); i += 2) { if (i == sb.length() - 1) sb.append(sb.length() % 2 == 1 ? 'X' : ""); else if (sb.charAt(i) == sb.charAt(i + 1)) sb.insert(i + 1, 'X'); } return codec(sb, 1); } private static String decode(String s) { return codec(new StringBuilder(s), 4); } private static String codec(StringBuilder text, int direction) { int len = text.length(); for (int i = 0; i < len; i += 2) { char a = text.charAt(i); char b = text.charAt(i + 1); int row1 = positions[a - 'A'].y; int row2 = positions[b - 'A'].y; int col1 = positions[a - 'A'].x; int col2 = positions[b - 'A'].x; if (row1 == row2) { col1 = (col1 + direction) % 5; col2 = (col2 + direction) % 5; } else if (col1 == col2) { row1 = (row1 + direction) % 5; row2 = (row2 + direction) % 5; } else { int tmp = col1; col1 = col2; col2 = tmp; } text.setCharAt(i, charTable[row1][col1]); text.setCharAt(i + 1, charTable[row2][col2]); } return text.toString(); } }
Ensure the translated Java code behaves exactly like the original Go snippet.
package main import ( "bufio" "fmt" "os" "strings" ) type playfairOption int const ( noQ playfairOption = iota iEqualsJ ) type playfair struct { keyword string pfo playfairOption table [5][5]byte } func (p *playfair) init() { var used [26]bool if p.pfo == noQ { used[16] = true } else { used[9] = true } alphabet := strings.ToUpper(p.keyword) + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" for i, j, k := 0, 0, 0; k < len(alphabet); k++ { c := alphabet[k] if c < 'A' || c > 'Z' { continue } d := int(c - 65) if !used[d] { p.table[i][j] = c used[d] = true j++ if j == 5 { i++ if i == 5 { break } j = 0 } } } } func (p *playfair) getCleanText(plainText string) string { plainText = strings.ToUpper(plainText) var cleanText strings.Builder prevByte := byte('\000') for i := 0; i < len(plainText); i++ { nextByte := plainText[i] if nextByte < 'A' || nextByte > 'Z' || (nextByte == 'Q' && p.pfo == noQ) { continue } if nextByte == 'J' && p.pfo == iEqualsJ { nextByte = 'I' } if nextByte != prevByte { cleanText.WriteByte(nextByte) } else { cleanText.WriteByte('X') cleanText.WriteByte(nextByte) } prevByte = nextByte } l := cleanText.Len() if l%2 == 1 { if cleanText.String()[l-1] != 'X' { cleanText.WriteByte('X') } else { cleanText.WriteByte('Z') } } return cleanText.String() } func (p *playfair) findByte(c byte) (int, int) { for i := 0; i < 5; i++ { for j := 0; j < 5; j++ { if p.table[i][j] == c { return i, j } } } return -1, -1 } func (p *playfair) encode(plainText string) string { cleanText := p.getCleanText(plainText) var cipherText strings.Builder l := len(cleanText) for i := 0; i < l; i += 2 { row1, col1 := p.findByte(cleanText[i]) row2, col2 := p.findByte(cleanText[i+1]) switch { case row1 == row2: cipherText.WriteByte(p.table[row1][(col1+1)%5]) cipherText.WriteByte(p.table[row2][(col2+1)%5]) case col1 == col2: cipherText.WriteByte(p.table[(row1+1)%5][col1]) cipherText.WriteByte(p.table[(row2+1)%5][col2]) default: cipherText.WriteByte(p.table[row1][col2]) cipherText.WriteByte(p.table[row2][col1]) } if i < l-1 { cipherText.WriteByte(' ') } } return cipherText.String() } func (p *playfair) decode(cipherText string) string { var decodedText strings.Builder l := len(cipherText) for i := 0; i < l; i += 3 { row1, col1 := p.findByte(cipherText[i]) row2, col2 := p.findByte(cipherText[i+1]) switch { case row1 == row2: temp := 4 if col1 > 0 { temp = col1 - 1 } decodedText.WriteByte(p.table[row1][temp]) temp = 4 if col2 > 0 { temp = col2 - 1 } decodedText.WriteByte(p.table[row2][temp]) case col1 == col2: temp := 4 if row1 > 0 { temp = row1 - 1 } decodedText.WriteByte(p.table[temp][col1]) temp = 4 if row2 > 0 { temp = row2 - 1 } decodedText.WriteByte(p.table[temp][col2]) default: decodedText.WriteByte(p.table[row1][col2]) decodedText.WriteByte(p.table[row2][col1]) } if i < l-1 { decodedText.WriteByte(' ') } } return decodedText.String() } func (p *playfair) printTable() { fmt.Println("The table to be used is :\n") for i := 0; i < 5; i++ { for j := 0; j < 5; j++ { fmt.Printf("%c ", p.table[i][j]) } fmt.Println() } } func main() { scanner := bufio.NewScanner(os.Stdin) fmt.Print("Enter Playfair keyword : ") scanner.Scan() keyword := scanner.Text() var ignoreQ string for ignoreQ != "y" && ignoreQ != "n" { fmt.Print("Ignore Q when building table y/n : ") scanner.Scan() ignoreQ = strings.ToLower(scanner.Text()) } pfo := noQ if ignoreQ == "n" { pfo = iEqualsJ } var table [5][5]byte pf := &playfair{keyword, pfo, table} pf.init() pf.printTable() fmt.Print("\nEnter plain text : ") scanner.Scan() plainText := scanner.Text() if err := scanner.Err(); err != nil { fmt.Fprintln(os.Stderr, "reading standard input:", err) return } encodedText := pf.encode(plainText) fmt.Println("\nEncoded text is :", encodedText) decodedText := pf.decode(encodedText) fmt.Println("Deccoded text is :", decodedText) }
import java.awt.Point; import java.util.Scanner; public class PlayfairCipher { private static char[][] charTable; private static Point[] positions; public static void main(String[] args) { Scanner sc = new Scanner(System.in); String key = prompt("Enter an encryption key (min length 6): ", sc, 6); String txt = prompt("Enter the message: ", sc, 1); String jti = prompt("Replace J with I? y/n: ", sc, 1); boolean changeJtoI = jti.equalsIgnoreCase("y"); createTable(key, changeJtoI); String enc = encode(prepareText(txt, changeJtoI)); System.out.printf("%nEncoded message: %n%s%n", enc); System.out.printf("%nDecoded message: %n%s%n", decode(enc)); } private static String prompt(String promptText, Scanner sc, int minLen) { String s; do { System.out.print(promptText); s = sc.nextLine().trim(); } while (s.length() < minLen); return s; } private static String prepareText(String s, boolean changeJtoI) { s = s.toUpperCase().replaceAll("[^A-Z]", ""); return changeJtoI ? s.replace("J", "I") : s.replace("Q", ""); } private static void createTable(String key, boolean changeJtoI) { charTable = new char[5][5]; positions = new Point[26]; String s = prepareText(key + "ABCDEFGHIJKLMNOPQRSTUVWXYZ", changeJtoI); int len = s.length(); for (int i = 0, k = 0; i < len; i++) { char c = s.charAt(i); if (positions[c - 'A'] == null) { charTable[k / 5][k % 5] = c; positions[c - 'A'] = new Point(k % 5, k / 5); k++; } } } private static String encode(String s) { StringBuilder sb = new StringBuilder(s); for (int i = 0; i < sb.length(); i += 2) { if (i == sb.length() - 1) sb.append(sb.length() % 2 == 1 ? 'X' : ""); else if (sb.charAt(i) == sb.charAt(i + 1)) sb.insert(i + 1, 'X'); } return codec(sb, 1); } private static String decode(String s) { return codec(new StringBuilder(s), 4); } private static String codec(StringBuilder text, int direction) { int len = text.length(); for (int i = 0; i < len; i += 2) { char a = text.charAt(i); char b = text.charAt(i + 1); int row1 = positions[a - 'A'].y; int row2 = positions[b - 'A'].y; int col1 = positions[a - 'A'].x; int col2 = positions[b - 'A'].x; if (row1 == row2) { col1 = (col1 + direction) % 5; col2 = (col2 + direction) % 5; } else if (col1 == col2) { row1 = (row1 + direction) % 5; row2 = (row2 + direction) % 5; } else { int tmp = col1; col1 = col2; col2 = tmp; } text.setCharAt(i, charTable[row1][col1]); text.setCharAt(i + 1, charTable[row2][col2]); } return text.toString(); } }
Rewrite this program in Java while keeping its functionality equivalent to the Go version.
package main import ( "bufio" "fmt" "os" "strings" ) type playfairOption int const ( noQ playfairOption = iota iEqualsJ ) type playfair struct { keyword string pfo playfairOption table [5][5]byte } func (p *playfair) init() { var used [26]bool if p.pfo == noQ { used[16] = true } else { used[9] = true } alphabet := strings.ToUpper(p.keyword) + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" for i, j, k := 0, 0, 0; k < len(alphabet); k++ { c := alphabet[k] if c < 'A' || c > 'Z' { continue } d := int(c - 65) if !used[d] { p.table[i][j] = c used[d] = true j++ if j == 5 { i++ if i == 5 { break } j = 0 } } } } func (p *playfair) getCleanText(plainText string) string { plainText = strings.ToUpper(plainText) var cleanText strings.Builder prevByte := byte('\000') for i := 0; i < len(plainText); i++ { nextByte := plainText[i] if nextByte < 'A' || nextByte > 'Z' || (nextByte == 'Q' && p.pfo == noQ) { continue } if nextByte == 'J' && p.pfo == iEqualsJ { nextByte = 'I' } if nextByte != prevByte { cleanText.WriteByte(nextByte) } else { cleanText.WriteByte('X') cleanText.WriteByte(nextByte) } prevByte = nextByte } l := cleanText.Len() if l%2 == 1 { if cleanText.String()[l-1] != 'X' { cleanText.WriteByte('X') } else { cleanText.WriteByte('Z') } } return cleanText.String() } func (p *playfair) findByte(c byte) (int, int) { for i := 0; i < 5; i++ { for j := 0; j < 5; j++ { if p.table[i][j] == c { return i, j } } } return -1, -1 } func (p *playfair) encode(plainText string) string { cleanText := p.getCleanText(plainText) var cipherText strings.Builder l := len(cleanText) for i := 0; i < l; i += 2 { row1, col1 := p.findByte(cleanText[i]) row2, col2 := p.findByte(cleanText[i+1]) switch { case row1 == row2: cipherText.WriteByte(p.table[row1][(col1+1)%5]) cipherText.WriteByte(p.table[row2][(col2+1)%5]) case col1 == col2: cipherText.WriteByte(p.table[(row1+1)%5][col1]) cipherText.WriteByte(p.table[(row2+1)%5][col2]) default: cipherText.WriteByte(p.table[row1][col2]) cipherText.WriteByte(p.table[row2][col1]) } if i < l-1 { cipherText.WriteByte(' ') } } return cipherText.String() } func (p *playfair) decode(cipherText string) string { var decodedText strings.Builder l := len(cipherText) for i := 0; i < l; i += 3 { row1, col1 := p.findByte(cipherText[i]) row2, col2 := p.findByte(cipherText[i+1]) switch { case row1 == row2: temp := 4 if col1 > 0 { temp = col1 - 1 } decodedText.WriteByte(p.table[row1][temp]) temp = 4 if col2 > 0 { temp = col2 - 1 } decodedText.WriteByte(p.table[row2][temp]) case col1 == col2: temp := 4 if row1 > 0 { temp = row1 - 1 } decodedText.WriteByte(p.table[temp][col1]) temp = 4 if row2 > 0 { temp = row2 - 1 } decodedText.WriteByte(p.table[temp][col2]) default: decodedText.WriteByte(p.table[row1][col2]) decodedText.WriteByte(p.table[row2][col1]) } if i < l-1 { decodedText.WriteByte(' ') } } return decodedText.String() } func (p *playfair) printTable() { fmt.Println("The table to be used is :\n") for i := 0; i < 5; i++ { for j := 0; j < 5; j++ { fmt.Printf("%c ", p.table[i][j]) } fmt.Println() } } func main() { scanner := bufio.NewScanner(os.Stdin) fmt.Print("Enter Playfair keyword : ") scanner.Scan() keyword := scanner.Text() var ignoreQ string for ignoreQ != "y" && ignoreQ != "n" { fmt.Print("Ignore Q when building table y/n : ") scanner.Scan() ignoreQ = strings.ToLower(scanner.Text()) } pfo := noQ if ignoreQ == "n" { pfo = iEqualsJ } var table [5][5]byte pf := &playfair{keyword, pfo, table} pf.init() pf.printTable() fmt.Print("\nEnter plain text : ") scanner.Scan() plainText := scanner.Text() if err := scanner.Err(); err != nil { fmt.Fprintln(os.Stderr, "reading standard input:", err) return } encodedText := pf.encode(plainText) fmt.Println("\nEncoded text is :", encodedText) decodedText := pf.decode(encodedText) fmt.Println("Deccoded text is :", decodedText) }
import java.awt.Point; import java.util.Scanner; public class PlayfairCipher { private static char[][] charTable; private static Point[] positions; public static void main(String[] args) { Scanner sc = new Scanner(System.in); String key = prompt("Enter an encryption key (min length 6): ", sc, 6); String txt = prompt("Enter the message: ", sc, 1); String jti = prompt("Replace J with I? y/n: ", sc, 1); boolean changeJtoI = jti.equalsIgnoreCase("y"); createTable(key, changeJtoI); String enc = encode(prepareText(txt, changeJtoI)); System.out.printf("%nEncoded message: %n%s%n", enc); System.out.printf("%nDecoded message: %n%s%n", decode(enc)); } private static String prompt(String promptText, Scanner sc, int minLen) { String s; do { System.out.print(promptText); s = sc.nextLine().trim(); } while (s.length() < minLen); return s; } private static String prepareText(String s, boolean changeJtoI) { s = s.toUpperCase().replaceAll("[^A-Z]", ""); return changeJtoI ? s.replace("J", "I") : s.replace("Q", ""); } private static void createTable(String key, boolean changeJtoI) { charTable = new char[5][5]; positions = new Point[26]; String s = prepareText(key + "ABCDEFGHIJKLMNOPQRSTUVWXYZ", changeJtoI); int len = s.length(); for (int i = 0, k = 0; i < len; i++) { char c = s.charAt(i); if (positions[c - 'A'] == null) { charTable[k / 5][k % 5] = c; positions[c - 'A'] = new Point(k % 5, k / 5); k++; } } } private static String encode(String s) { StringBuilder sb = new StringBuilder(s); for (int i = 0; i < sb.length(); i += 2) { if (i == sb.length() - 1) sb.append(sb.length() % 2 == 1 ? 'X' : ""); else if (sb.charAt(i) == sb.charAt(i + 1)) sb.insert(i + 1, 'X'); } return codec(sb, 1); } private static String decode(String s) { return codec(new StringBuilder(s), 4); } private static String codec(StringBuilder text, int direction) { int len = text.length(); for (int i = 0; i < len; i += 2) { char a = text.charAt(i); char b = text.charAt(i + 1); int row1 = positions[a - 'A'].y; int row2 = positions[b - 'A'].y; int col1 = positions[a - 'A'].x; int col2 = positions[b - 'A'].x; if (row1 == row2) { col1 = (col1 + direction) % 5; col2 = (col2 + direction) % 5; } else if (col1 == col2) { row1 = (row1 + direction) % 5; row2 = (row2 + direction) % 5; } else { int tmp = col1; col1 = col2; col2 = tmp; } text.setCharAt(i, charTable[row1][col1]); text.setCharAt(i + 1, charTable[row2][col2]); } return text.toString(); } }
Port the provided Go code into Java while preserving the original functionality.
package main import ( "fmt" "math" "math/rand" "time" ) type xy struct { x, y float64 } const n = 1000 const scale = 100. func d(p1, p2 xy) float64 { return math.Hypot(p2.x-p1.x, p2.y-p1.y) } func main() { rand.Seed(time.Now().Unix()) points := make([]xy, n) for i := range points { points[i] = xy{rand.Float64() * scale, rand.Float64() * scale} } p1, p2 := closestPair(points) fmt.Println(p1, p2) fmt.Println("distance:", d(p1, p2)) } func closestPair(points []xy) (p1, p2 xy) { if len(points) < 2 { panic("at least two points expected") } min := 2 * scale for i, q1 := range points[:len(points)-1] { for _, q2 := range points[i+1:] { if dq := d(q1, q2); dq < min { p1, p2 = q1, q2 min = dq } } } return }
import java.util.*; public class ClosestPair { public static class Point { public final double x; public final double y; public Point(double x, double y) { this.x = x; this.y = y; } public String toString() { return "(" + x + ", " + y + ")"; } } public static class Pair { public Point point1 = null; public Point point2 = null; public double distance = 0.0; public Pair() { } public Pair(Point point1, Point point2) { this.point1 = point1; this.point2 = point2; calcDistance(); } public void update(Point point1, Point point2, double distance) { this.point1 = point1; this.point2 = point2; this.distance = distance; } public void calcDistance() { this.distance = distance(point1, point2); } public String toString() { return point1 + "-" + point2 + " : " + distance; } } public static double distance(Point p1, Point p2) { double xdist = p2.x - p1.x; double ydist = p2.y - p1.y; return Math.hypot(xdist, ydist); } public static Pair bruteForce(List<? extends Point> points) { int numPoints = points.size(); if (numPoints < 2) return null; Pair pair = new Pair(points.get(0), points.get(1)); if (numPoints > 2) { for (int i = 0; i < numPoints - 1; i++) { Point point1 = points.get(i); for (int j = i + 1; j < numPoints; j++) { Point point2 = points.get(j); double distance = distance(point1, point2); if (distance < pair.distance) pair.update(point1, point2, distance); } } } return pair; } public static void sortByX(List<? extends Point> points) { Collections.sort(points, new Comparator<Point>() { public int compare(Point point1, Point point2) { if (point1.x < point2.x) return -1; if (point1.x > point2.x) return 1; return 0; } } ); } public static void sortByY(List<? extends Point> points) { Collections.sort(points, new Comparator<Point>() { public int compare(Point point1, Point point2) { if (point1.y < point2.y) return -1; if (point1.y > point2.y) return 1; return 0; } } ); } public static Pair divideAndConquer(List<? extends Point> points) { List<Point> pointsSortedByX = new ArrayList<Point>(points); sortByX(pointsSortedByX); List<Point> pointsSortedByY = new ArrayList<Point>(points); sortByY(pointsSortedByY); return divideAndConquer(pointsSortedByX, pointsSortedByY); } private static Pair divideAndConquer(List<? extends Point> pointsSortedByX, List<? extends Point> pointsSortedByY) { int numPoints = pointsSortedByX.size(); if (numPoints <= 3) return bruteForce(pointsSortedByX); int dividingIndex = numPoints >>> 1; List<? extends Point> leftOfCenter = pointsSortedByX.subList(0, dividingIndex); List<? extends Point> rightOfCenter = pointsSortedByX.subList(dividingIndex, numPoints); List<Point> tempList = new ArrayList<Point>(leftOfCenter); sortByY(tempList); Pair closestPair = divideAndConquer(leftOfCenter, tempList); tempList.clear(); tempList.addAll(rightOfCenter); sortByY(tempList); Pair closestPairRight = divideAndConquer(rightOfCenter, tempList); if (closestPairRight.distance < closestPair.distance) closestPair = closestPairRight; tempList.clear(); double shortestDistance =closestPair.distance; double centerX = rightOfCenter.get(0).x; for (Point point : pointsSortedByY) if (Math.abs(centerX - point.x) < shortestDistance) tempList.add(point); for (int i = 0; i < tempList.size() - 1; i++) { Point point1 = tempList.get(i); for (int j = i + 1; j < tempList.size(); j++) { Point point2 = tempList.get(j); if ((point2.y - point1.y) >= shortestDistance) break; double distance = distance(point1, point2); if (distance < closestPair.distance) { closestPair.update(point1, point2, distance); shortestDistance = distance; } } } return closestPair; } public static void main(String[] args) { int numPoints = (args.length == 0) ? 1000 : Integer.parseInt(args[0]); List<Point> points = new ArrayList<Point>(); Random r = new Random(); for (int i = 0; i < numPoints; i++) points.add(new Point(r.nextDouble(), r.nextDouble())); System.out.println("Generated " + numPoints + " random points"); long startTime = System.currentTimeMillis(); Pair bruteForceClosestPair = bruteForce(points); long elapsedTime = System.currentTimeMillis() - startTime; System.out.println("Brute force (" + elapsedTime + " ms): " + bruteForceClosestPair); startTime = System.currentTimeMillis(); Pair dqClosestPair = divideAndConquer(points); elapsedTime = System.currentTimeMillis() - startTime; System.out.println("Divide and conquer (" + elapsedTime + " ms): " + dqClosestPair); if (bruteForceClosestPair.distance != dqClosestPair.distance) System.out.println("MISMATCH"); } }
Write a version of this Go function in Java with identical behavior.
package main type animal struct { alive bool } type dog struct { animal obedienceTrained bool } type cat struct { animal litterBoxTrained bool } type lab struct { dog color string } type collie struct { dog catchesFrisbee bool } func main() { var pet lab pet.alive = true pet.obedienceTrained = false pet.color = "yellow" }
public class Animal{ }
Write the same algorithm in Java as shown in this Go implementation.
var x map[string]int x = make(map[string]int) x = make(map[string]int, 42) x["foo"] = 3 y1 := x["bar"] y2, ok := x["bar"] delete(x, "foo") x = map[string]int{ "foo": 2, "bar": 42, "baz": -1, }
Map<String, Int> map = new HashMap(); map["foo"] = 5; map["bar"] = 10; map["baz"] = 15; map["foo"] = 6;
Convert this Go snippet to Java and keep its semantics consistent.
package main import ( "fmt" "math/big" "rcu" ) func main() { const LIMIT = 11000 primes := rcu.Primes(LIMIT) facts := make([]*big.Int, LIMIT) facts[0] = big.NewInt(1) for i := int64(1); i < LIMIT; i++ { facts[i] = new(big.Int) facts[i].Mul(facts[i-1], big.NewInt(i)) } sign := int64(1) f := new(big.Int) zero := new(big.Int) fmt.Println(" n: Wilson primes") fmt.Println("--------------------") for n := 1; n < 12; n++ { fmt.Printf("%2d: ", n) sign = -sign for _, p := range primes { if p < n { continue } f.Mul(facts[n-1], facts[p-n]) f.Sub(f, big.NewInt(sign)) p2 := int64(p * p) bp2 := big.NewInt(p2) if f.Rem(f, bp2).Cmp(zero) == 0 { fmt.Printf("%d ", p) } } fmt.Println() } }
import java.math.BigInteger; import java.util.*; public class WilsonPrimes { public static void main(String[] args) { final int limit = 11000; BigInteger[] f = new BigInteger[limit]; f[0] = BigInteger.ONE; BigInteger factorial = BigInteger.ONE; for (int i = 1; i < limit; ++i) { factorial = factorial.multiply(BigInteger.valueOf(i)); f[i] = factorial; } List<Integer> primes = generatePrimes(limit); System.out.printf(" n | Wilson primes\n--------------------\n"); BigInteger s = BigInteger.valueOf(-1); for (int n = 1; n <= 11; ++n) { System.out.printf("%2d |", n); for (int p : primes) { if (p >= n && f[n - 1].multiply(f[p - n]).subtract(s) .mod(BigInteger.valueOf(p * p)) .equals(BigInteger.ZERO)) System.out.printf(" %d", p); } s = s.negate(); System.out.println(); } } private static List<Integer> generatePrimes(int limit) { boolean[] sieve = new boolean[limit >> 1]; Arrays.fill(sieve, true); for (int p = 3, s = 9; s < limit; p += 2) { if (sieve[p >> 1]) { for (int q = s; q < limit; q += p << 1) sieve[q >> 1] = false; } s += (p + 1) << 2; } List<Integer> primes = new ArrayList<>(); if (limit > 2) primes.add(2); for (int i = 1; i < sieve.length; ++i) { if (sieve[i]) primes.add((i << 1) + 1); } return primes; } }
Write the same code in Java as shown below in Go.
package main import ( "github.com/fogleman/gg" "math" ) const tau = 2 * math.Pi func hsb2rgb(hue, sat, bri float64) (r, g, b int) { u := int(bri*255 + 0.5) if sat == 0 { r, g, b = u, u, u } else { h := (hue - math.Floor(hue)) * 6 f := h - math.Floor(h) p := int(bri*(1-sat)*255 + 0.5) q := int(bri*(1-sat*f)*255 + 0.5) t := int(bri*(1-sat*(1-f))*255 + 0.5) switch int(h) { case 0: r, g, b = u, t, p case 1: r, g, b = q, u, p case 2: r, g, b = p, u, t case 3: r, g, b = p, q, u case 4: r, g, b = t, p, u case 5: r, g, b = u, p, q } } return } func colorWheel(dc *gg.Context) { width, height := dc.Width(), dc.Height() centerX, centerY := width/2, height/2 radius := centerX if centerY < radius { radius = centerY } for y := 0; y < height; y++ { dy := float64(y - centerY) for x := 0; x < width; x++ { dx := float64(x - centerX) dist := math.Sqrt(dx*dx + dy*dy) if dist <= float64(radius) { theta := math.Atan2(dy, dx) hue := (theta + math.Pi) / tau r, g, b := hsb2rgb(hue, 1, 1) dc.SetRGB255(r, g, b) dc.SetPixel(x, y) } } } } func main() { const width, height = 480, 480 dc := gg.NewContext(width, height) dc.SetRGB(1, 1, 1) dc.Clear() colorWheel(dc) dc.SavePNG("color_wheel.png") }
import java.awt.*; import javax.swing.*; public class ColorWheel { public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { ColorWheelFrame frame = new ColorWheelFrame(); frame.setVisible(true); } }); } private static class ColorWheelFrame extends JFrame { private ColorWheelFrame() { super("Color Wheel"); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); getContentPane().add(new ColorWheelPanel()); pack(); } } private static class ColorWheelPanel extends JComponent { private ColorWheelPanel() { setPreferredSize(new Dimension(400, 400)); } public void paint(Graphics g) { Graphics2D g2 = (Graphics2D)g; int w = getWidth(); int h = getHeight(); int margin = 10; int radius = (Math.min(w, h) - 2 * margin)/2; int cx = w/2; int cy = h/2; float[] dist = {0.F, 1.0F}; g2.setColor(Color.BLACK); g2.fillRect(0, 0, w, h); for (int angle = 0; angle < 360; ++angle) { Color color = hsvToRgb(angle, 1.0, 1.0); Color[] colors = {Color.WHITE, color}; RadialGradientPaint paint = new RadialGradientPaint(cx, cy, radius, dist, colors); g2.setPaint(paint); g2.fillArc(cx - radius, cy - radius, radius*2, radius*2, angle, 1); } } } private static Color hsvToRgb(int h, double s, double v) { double hp = h/60.0; double c = s * v; double x = c * (1 - Math.abs(hp % 2.0 - 1)); double m = v - c; double r = 0, g = 0, b = 0; if (hp <= 1) { r = c; g = x; } else if (hp <= 2) { r = x; g = c; } else if (hp <= 3) { g = c; b = x; } else if (hp <= 4) { g = x; b = c; } else if (hp <= 5) { r = x; b = c; } else { r = c; b = x; } r += m; g += m; b += m; return new Color((int)(r * 255), (int)(g * 255), (int)(b * 255)); } }
Ensure the translated Java code behaves exactly like the original Go snippet.
package main import ( "image" "image/color" "image/gif" "log" "math" "os" ) func setBackgroundColor(img *image.Paletted, w, h int, ci uint8) { for x := 0; x < w; x++ { for y := 0; y < h; y++ { img.SetColorIndex(x, y, ci) } } } func hsb2rgb(hue, sat, bri float64) (r, g, b int) { u := int(bri*255 + 0.5) if sat == 0 { r, g, b = u, u, u } else { h := (hue - math.Floor(hue)) * 6 f := h - math.Floor(h) p := int(bri*(1-sat)*255 + 0.5) q := int(bri*(1-sat*f)*255 + 0.5) t := int(bri*(1-sat*(1-f))*255 + 0.5) switch int(h) { case 0: r, g, b = u, t, p case 1: r, g, b = q, u, p case 2: r, g, b = p, u, t case 3: r, g, b = p, q, u case 4: r, g, b = t, p, u case 5: r, g, b = u, p, q } } return } func main() { const degToRad = math.Pi / 180 const nframes = 100 const delay = 4 w, h := 640, 640 anim := gif.GIF{LoopCount: nframes} rect := image.Rect(0, 0, w, h) palette := make([]color.Color, nframes+1) palette[0] = color.White for i := 1; i <= nframes; i++ { r, g, b := hsb2rgb(float64(i)/nframes, 1, 1) palette[i] = color.RGBA{uint8(r), uint8(g), uint8(b), 255} } for f := 1; f <= nframes; f++ { img := image.NewPaletted(rect, palette) setBackgroundColor(img, w, h, 0) for y := 0; y < h; y++ { for x := 0; x < w; x++ { fx, fy := float64(x), float64(y) value := math.Sin(fx / 16) value += math.Sin(fy / 8) value += math.Sin((fx + fy) / 16) value += math.Sin(math.Sqrt(fx*fx+fy*fy) / 8) value += 4 value /= 8 _, rem := math.Modf(value + float64(f)/float64(nframes)) ci := uint8(nframes*rem) + 1 img.SetColorIndex(x, y, ci) } } anim.Delay = append(anim.Delay, delay) anim.Image = append(anim.Image, img) } file, err := os.Create("plasma.gif") if err != nil { log.Fatal(err) } defer file.Close() if err2 := gif.EncodeAll(file, &anim); err != nil { log.Fatal(err2) } }
import java.awt.*; import java.awt.event.*; import java.awt.image.*; import static java.awt.image.BufferedImage.*; import static java.lang.Math.*; import javax.swing.*; public class PlasmaEffect extends JPanel { float[][] plasma; float hueShift = 0; BufferedImage img; public PlasmaEffect() { Dimension dim = new Dimension(640, 640); setPreferredSize(dim); setBackground(Color.white); img = new BufferedImage(dim.width, dim.height, TYPE_INT_RGB); plasma = createPlasma(dim.height, dim.width); new Timer(42, (ActionEvent e) -> { hueShift = (hueShift + 0.02f) % 1; repaint(); }).start(); } float[][] createPlasma(int w, int h) { float[][] buffer = new float[h][w]; for (int y = 0; y < h; y++) for (int x = 0; x < w; x++) { double value = sin(x / 16.0); value += sin(y / 8.0); value += sin((x + y) / 16.0); value += sin(sqrt(x * x + y * y) / 8.0); value += 4; value /= 8; assert (value >= 0.0 && value <= 1.0) : "Hue value out of bounds"; buffer[y][x] = (float) value; } return buffer; } void drawPlasma(Graphics2D g) { int h = plasma.length; int w = plasma[0].length; for (int y = 0; y < h; y++) for (int x = 0; x < w; x++) { float hue = hueShift + plasma[y][x] % 1; img.setRGB(x, y, Color.HSBtoRGB(hue, 1, 1)); } g.drawImage(img, 0, 0, null); } @Override public void paintComponent(Graphics gg) { super.paintComponent(gg); Graphics2D g = (Graphics2D) gg; g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); drawPlasma(g); } public static void main(String[] args) { SwingUtilities.invokeLater(() -> { JFrame f = new JFrame(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setTitle("Plasma Effect"); f.setResizable(false); f.add(new PlasmaEffect(), BorderLayout.CENTER); f.pack(); f.setLocationRelativeTo(null); f.setVisible(true); }); } }
Port the provided Go code into Java while preserving the original functionality.
package main import ( "fmt" "rcu" "strconv" ) func contains(a []int, n int) bool { for _, e := range a { if e == n { return true } } return false } func main() { for b := 2; b <= 36; b++ { if rcu.IsPrime(b) { continue } count := 0 var rhonda []int for n := 1; count < 15; n++ { digits := rcu.Digits(n, b) if !contains(digits, 0) { var anyEven = false for _, d := range digits { if d%2 == 0 { anyEven = true break } } if b != 10 || (contains(digits, 5) && anyEven) { calc1 := 1 for _, d := range digits { calc1 *= d } calc2 := b * rcu.SumInts(rcu.PrimeFactors(n)) if calc1 == calc2 { rhonda = append(rhonda, n) count++ } } } } if len(rhonda) > 0 { fmt.Printf("\nFirst 15 Rhonda numbers in base %d:\n", b) rhonda2 := make([]string, len(rhonda)) counts2 := make([]int, len(rhonda)) for i, r := range rhonda { rhonda2[i] = fmt.Sprintf("%d", r) counts2[i] = len(rhonda2[i]) } rhonda3 := make([]string, len(rhonda)) counts3 := make([]int, len(rhonda)) for i, r := range rhonda { rhonda3[i] = strconv.FormatInt(int64(r), b) counts3[i] = len(rhonda3[i]) } maxLen2 := rcu.MaxInts(counts2) maxLen3 := rcu.MaxInts(counts3) maxLen := maxLen2 if maxLen3 > maxLen { maxLen = maxLen3 } maxLen++ fmt.Printf("In base 10: %*s\n", maxLen, rhonda2) fmt.Printf("In base %-2d: %*s\n", b, maxLen, rhonda3) } } }
public class RhondaNumbers { public static void main(String[] args) { final int limit = 15; for (int base = 2; base <= 36; ++base) { if (isPrime(base)) continue; System.out.printf("First %d Rhonda numbers to base %d:\n", limit, base); int numbers[] = new int[limit]; for (int n = 1, count = 0; count < limit; ++n) { if (isRhonda(base, n)) numbers[count++] = n; } System.out.printf("In base 10:"); for (int i = 0; i < limit; ++i) System.out.printf(" %d", numbers[i]); System.out.printf("\nIn base %d:", base); for (int i = 0; i < limit; ++i) System.out.printf(" %s", Integer.toString(numbers[i], base)); System.out.printf("\n\n"); } } private static int digitProduct(int base, int n) { int product = 1; for (; n != 0; n /= base) product *= n % base; return product; } private static int primeFactorSum(int n) { int sum = 0; for (; (n & 1) == 0; n >>= 1) sum += 2; for (int p = 3; p * p <= n; p += 2) for (; n % p == 0; n /= p) sum += p; if (n > 1) sum += n; return sum; } private static boolean isPrime(int n) { if (n < 2) return false; if (n % 2 == 0) return n == 2; if (n % 3 == 0) return n == 3; for (int p = 5; p * p <= n; p += 4) { if (n % p == 0) return false; p += 2; if (n % p == 0) return false; } return true; } private static boolean isRhonda(int base, int n) { return digitProduct(base, n) == base * primeFactorSum(n); } }
Write the same algorithm in Java as shown in this Go implementation.
package main import "fmt" type point struct { x, y float64 } type circle struct { x, y, r float64 } type printer interface { print() } func (p *point) print() { fmt.Println(p.x, p.y) } func (c *circle) print() { fmt.Println(c.x, c.y, c.r) } func main() { var i printer i = newPoint(3, 4) i.print() i = newCircle(5, 12, 13) i.print() } func (p *point) getX() float64 { return p.x } func (p *point) getY() float64 { return p.y } func (p *point) setX(v float64) { p.x = v } func (p *point) setY(v float64) { p.y = v } func (c *circle) getX() float64 { return c.x } func (c *circle) getY() float64 { return c.y } func (c *circle) getR() float64 { return c.r } func (c *circle) setX(v float64) { c.x = v } func (c *circle) setY(v float64) { c.y = v } func (c *circle) setR(v float64) { c.r = v } func (p *point) clone() *point { r := *p; return &r } func (c *circle) clone() *circle { r := *c; return &r } func (p *point) set(q *point) { *p = *q } func (c *circle) set(d *circle) { *c = *d } func newPoint(x, y float64) *point { return &point{x, y} } func newCircle(x, y, r float64) *circle { return &circle{x, y, r} }
class Point { protected int x, y; public Point() { this(0); } public Point(int x) { this(x, 0); } public Point(int x, int y) { this.x = x; this.y = y; } public Point(Point p) { this(p.x, p.y); } public int getX() { return this.x; } public int getY() { return this.y; } public void setX(int x) { this.x = x; } public void setY(int y) { this.y = y; } public void print() { System.out.println("Point x: " + this.x + " y: " + this.y); } } class Circle extends Point { private int r; public Circle(Point p) { this(p, 0); } public Circle(Point p, int r) { super(p); this.r = r; } public Circle() { this(0); } public Circle(int x) { this(x, 0); } public Circle(int x, int y) { this(x, y, 0); } public Circle(int x, int y, int r) { super(x, y); this.r = r; } public Circle(Circle c) { this(c.x, c.y, c.r); } public int getR() { return this.r; } public void setR(int r) { this.r = r; } public void print() { System.out.println("Circle x: " + this.x + " y: " + this.y + " r: " + this.r); } } public class test { public static void main(String args[]) { Point p = new Point(); Point c = new Circle(); p.print(); c.print(); } }
Maintain the same structure and functionality when rewriting this code in Java.
package romap type Romap struct{ imap map[byte]int } func New(m map[byte]int) *Romap { if m == nil { return nil } return &Romap{m} } func (rom *Romap) Get(key byte) (int, bool) { i, ok := rom.imap[key] return i, ok } func (rom *Romap) Reset(key byte) { _, ok := rom.imap[key] if ok { rom.imap[key] = 0 } }
import java.util.Collections; import java.util.HashMap; import java.util.Map; public class ImmutableMap { public static void main(String[] args) { Map<String,Integer> hashMap = getImmutableMap(); try { hashMap.put("Test", 23); } catch (UnsupportedOperationException e) { System.out.println("ERROR: Unable to put new value."); } try { hashMap.clear(); } catch (UnsupportedOperationException e) { System.out.println("ERROR: Unable to clear map."); } try { hashMap.putIfAbsent("Test", 23); } catch (UnsupportedOperationException e) { System.out.println("ERROR: Unable to put if absent."); } for ( String key : hashMap.keySet() ) { System.out.printf("key = %s, value = %s%n", key, hashMap.get(key)); } } private static Map<String,Integer> getImmutableMap() { Map<String,Integer> hashMap = new HashMap<>(); hashMap.put("Key 1", 34); hashMap.put("Key 2", 105); hashMap.put("Key 3", 144); return Collections.unmodifiableMap(hashMap); } }
Keep all operations the same but rewrite the snippet in Java.
package main import ( "fmt" "github.com/atotto/clipboard" "io/ioutil" "log" "os" "runtime" "strconv" "strings" ) func check(err error) { if err != nil { clipboard.WriteAll("") log.Fatal(err) } } func interpret(source string) { source2 := source if runtime.GOOS == "windows" { source2 = strings.ReplaceAll(source, "\r\n", "\n") } lines := strings.Split(source2, "\n") le := len(lines) for i := 0; i < le; i++ { lines[i] = strings.TrimSpace(lines[i]) switch lines[i] { case "Copy": if i == le-1 { log.Fatal("There are no lines after the Copy command.") } i++ err := clipboard.WriteAll(lines[i]) check(err) case "CopyFile": if i == le-1 { log.Fatal("There are no lines after the CopyFile command.") } i++ if lines[i] == "TheF*ckingCode" { err := clipboard.WriteAll(source) check(err) } else { bytes, err := ioutil.ReadFile(lines[i]) check(err) err = clipboard.WriteAll(string(bytes)) check(err) } case "Duplicate": if i == le-1 { log.Fatal("There are no lines after the Duplicate command.") } i++ times, err := strconv.Atoi(lines[i]) check(err) if times < 0 { log.Fatal("Can't duplicate text a negative number of times.") } text, err := clipboard.ReadAll() check(err) err = clipboard.WriteAll(strings.Repeat(text, times+1)) check(err) case "Pasta!": text, err := clipboard.ReadAll() check(err) fmt.Println(text) return default: if lines[i] == "" { continue } log.Fatal("Unknown command, " + lines[i]) } } } func main() { if len(os.Args) != 2 { log.Fatal("There should be exactly one command line argument, the CopyPasta file path.") } bytes, err := ioutil.ReadFile(os.Args[1]) check(err) interpret(string(bytes)) err = clipboard.WriteAll("") check(err) }
import java.io.File; import java.nio.file.Files; import java.util.ArrayList; import java.util.Arrays; public class Copypasta { public static void fatal_error(String errtext) { StackTraceElement[] stack = Thread.currentThread().getStackTrace(); StackTraceElement main = stack[stack.length - 1]; String mainClass = main.getClassName(); System.out.println("%" + errtext); System.out.println("usage: " + mainClass + " [filename.cp]"); System.exit(1); } public static void main(String[] args) { String fname = null; String source = null; try { fname = args[0]; source = new String(Files.readAllBytes(new File(fname).toPath())); } catch(Exception e) { fatal_error("error while trying to read from specified file"); } ArrayList<String> lines = new ArrayList<String>(Arrays.asList(source.split("\n"))); String clipboard = ""; int loc = 0; while(loc < lines.size()) { String command = lines.get(loc).trim(); try { if(command.equals("Copy")) clipboard += lines.get(loc + 1); else if(command.equals("CopyFile")) { if(lines.get(loc + 1).equals("TheF*ckingCode")) clipboard += source; else { String filetext = new String(Files.readAllBytes(new File(lines.get(loc + 1)).toPath())); clipboard += filetext; } } else if(command.equals("Duplicate")) { String origClipboard = clipboard; int amount = Integer.parseInt(lines.get(loc + 1)) - 1; for(int i = 0; i < amount; i++) clipboard += origClipboard; } else if(command.equals("Pasta!")) { System.out.println(clipboard); System.exit(0); } else fatal_error("unknown command '" + command + "' encountered on line " + new Integer(loc + 1).toString()); } catch(Exception e) { fatal_error("error while executing command '" + command + "' on line " + new Integer(loc + 1).toString()); } loc += 2; } } }
Translate this program into Java but keep the logic exactly as in Go.
package main import ( "fmt" "math/big" ) var one = big.NewInt(1) var ten = big.NewInt(10) var twenty = big.NewInt(20) var hundred = big.NewInt(100) func sqrt(n float64, limit int) { if n < 0 { log.Fatal("Number cannot be negative") } count := 0 for n != math.Trunc(n) { n *= 100 count-- } i := big.NewInt(int64(n)) j := new(big.Int).Sqrt(i) count += len(j.String()) k := new(big.Int).Set(j) d := new(big.Int).Set(j) t := new(big.Int) digits := 0 var sb strings.Builder for digits < limit { sb.WriteString(d.String()) t.Mul(k, d) i.Sub(i, t) i.Mul(i, hundred) k.Mul(j, twenty) d.Set(one) for d.Cmp(ten) <= 0 { t.Add(k, d) t.Mul(t, d) if t.Cmp(i) > 0 { d.Sub(d, one) break } d.Add(d, one) } j.Mul(j, ten) j.Add(j, d) k.Add(k, d) digits = digits + 1 } root := strings.TrimRight(sb.String(), "0") if len(root) == 0 { root = "0" } if count > 0 { root = root[0:count] + "." + root[count:] } else if count == 0 { root = "0." + root } else { root = "0." + strings.Repeat("0", -count) + root } root = strings.TrimSuffix(root, ".") fmt.Println(root) } func main() { numbers := []float64{2, 0.2, 10.89, 625, 0.0001} digits := []int{500, 80, 8, 8, 8} for i, n := range numbers { fmt.Printf("First %d significant digits (at most) of the square root of %g:\n", digits[i], n) sqrt(n, digits[i]) fmt.Println() } }
import java.math.BigInteger; public class SquareRoot { public static final BigInteger ONE_HUNDRED = BigInteger.valueOf(100); public static final BigInteger TWENTY = BigInteger.valueOf(20); public static void main(String[] args) { var i = BigInteger.TWO; var j = BigInteger.valueOf((long) Math.floor(Math.sqrt(2.0))); var k = j; var d = j; int n = 500; int n0 = n; do { System.out.print(d); i = i.subtract(k.multiply(d)).multiply(ONE_HUNDRED); k = TWENTY.multiply(j); for (d = BigInteger.ONE; d.compareTo(BigInteger.TEN) <= 0; d = d.add(BigInteger.ONE)) { if (k.add(d).multiply(d).compareTo(i) > 0) { d = d.subtract(BigInteger.ONE); break; } } j = j.multiply(BigInteger.TEN).add(d); k = k.add(d); if (n0 > 0) { n--; } } while (n > 0); System.out.println(); } }
Maintain the same structure and functionality when rewriting this code in Java.
package main import ( "fmt" "math/big" ) var one = big.NewInt(1) var ten = big.NewInt(10) var twenty = big.NewInt(20) var hundred = big.NewInt(100) func sqrt(n float64, limit int) { if n < 0 { log.Fatal("Number cannot be negative") } count := 0 for n != math.Trunc(n) { n *= 100 count-- } i := big.NewInt(int64(n)) j := new(big.Int).Sqrt(i) count += len(j.String()) k := new(big.Int).Set(j) d := new(big.Int).Set(j) t := new(big.Int) digits := 0 var sb strings.Builder for digits < limit { sb.WriteString(d.String()) t.Mul(k, d) i.Sub(i, t) i.Mul(i, hundred) k.Mul(j, twenty) d.Set(one) for d.Cmp(ten) <= 0 { t.Add(k, d) t.Mul(t, d) if t.Cmp(i) > 0 { d.Sub(d, one) break } d.Add(d, one) } j.Mul(j, ten) j.Add(j, d) k.Add(k, d) digits = digits + 1 } root := strings.TrimRight(sb.String(), "0") if len(root) == 0 { root = "0" } if count > 0 { root = root[0:count] + "." + root[count:] } else if count == 0 { root = "0." + root } else { root = "0." + strings.Repeat("0", -count) + root } root = strings.TrimSuffix(root, ".") fmt.Println(root) } func main() { numbers := []float64{2, 0.2, 10.89, 625, 0.0001} digits := []int{500, 80, 8, 8, 8} for i, n := range numbers { fmt.Printf("First %d significant digits (at most) of the square root of %g:\n", digits[i], n) sqrt(n, digits[i]) fmt.Println() } }
import java.math.BigInteger; public class SquareRoot { public static final BigInteger ONE_HUNDRED = BigInteger.valueOf(100); public static final BigInteger TWENTY = BigInteger.valueOf(20); public static void main(String[] args) { var i = BigInteger.TWO; var j = BigInteger.valueOf((long) Math.floor(Math.sqrt(2.0))); var k = j; var d = j; int n = 500; int n0 = n; do { System.out.print(d); i = i.subtract(k.multiply(d)).multiply(ONE_HUNDRED); k = TWENTY.multiply(j); for (d = BigInteger.ONE; d.compareTo(BigInteger.TEN) <= 0; d = d.add(BigInteger.ONE)) { if (k.add(d).multiply(d).compareTo(i) > 0) { d = d.subtract(BigInteger.ONE); break; } } j = j.multiply(BigInteger.TEN).add(d); k = k.add(d); if (n0 > 0) { n--; } } while (n > 0); System.out.println(); } }
Rewrite the snippet below in Java so it works the same as the original Go code.
package main import ( "fmt" "image" "reflect" ) type t struct { X int next *t } func main() { report(t{}) report(image.Point{}) } func report(x interface{}) { t := reflect.TypeOf(x) n := t.NumField() fmt.Printf("Type %v has %d fields:\n", t, n) fmt.Println("Name Type Exported") for i := 0; i < n; i++ { f := t.Field(i) fmt.Printf("%-8s %-8v %-8t\n", f.Name, f.Type, f.PkgPath == "", ) } fmt.Println() }
import java.lang.reflect.Field; public class ListFields { public int examplePublicField = 42; private boolean examplePrivateField = true; public static void main(String[] args) throws IllegalAccessException { ListFields obj = new ListFields(); Class clazz = obj.getClass(); System.out.println("All public fields (including inherited):"); for (Field f : clazz.getFields()) { System.out.printf("%s\t%s\n", f, f.get(obj)); } System.out.println(); System.out.println("All declared fields (excluding inherited):"); for (Field f : clazz.getDeclaredFields()) { System.out.printf("%s\t%s\n", f, f.get(obj)); } } }
Generate an equivalent Java version of this Go code.
package main import ( "fmt" "strings" ) const limit = 50000 var ( divs, subs []int mins [][]string ) func minsteps(n int) { if n == 1 { mins[1] = []string{} return } min := limit var p, q int var op byte for _, div := range divs { if n%div == 0 { d := n / div steps := len(mins[d]) + 1 if steps < min { min = steps p, q, op = d, div, '/' } } } for _, sub := range subs { if d := n - sub; d >= 1 { steps := len(mins[d]) + 1 if steps < min { min = steps p, q, op = d, sub, '-' } } } mins[n] = append(mins[n], fmt.Sprintf("%c%d -> %d", op, q, p)) mins[n] = append(mins[n], mins[p]...) } func main() { for r := 0; r < 2; r++ { divs = []int{2, 3} if r == 0 { subs = []int{1} } else { subs = []int{2} } mins = make([][]string, limit+1) fmt.Printf("With: Divisors: %v, Subtractors: %v =>\n", divs, subs) fmt.Println(" Minimum number of steps to diminish the following numbers down to 1 is:") for i := 1; i <= limit; i++ { minsteps(i) if i <= 10 { steps := len(mins[i]) plural := "s" if steps == 1 { plural = " " } fmt.Printf(" %2d: %d step%s: %s\n", i, steps, plural, strings.Join(mins[i], ", ")) } } for _, lim := range []int{2000, 20000, 50000} { max := 0 for _, min := range mins[0 : lim+1] { m := len(min) if m > max { max = m } } var maxs []int for i, min := range mins[0 : lim+1] { if len(min) == max { maxs = append(maxs, i) } } nums := len(maxs) verb, verb2, plural := "are", "have", "s" if nums == 1 { verb, verb2, plural = "is", "has", "" } fmt.Printf(" There %s %d number%s in the range 1-%d ", verb, nums, plural, lim) fmt.Printf("that %s maximum 'minimal steps' of %d:\n", verb2, max) fmt.Println(" ", maxs) } fmt.Println() } }
import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; public class MinimalStepsDownToOne { public static void main(String[] args) { runTasks(getFunctions1()); runTasks(getFunctions2()); runTasks(getFunctions3()); } private static void runTasks(List<Function> functions) { Map<Integer,List<String>> minPath = getInitialMap(functions, 5); int max = 10; populateMap(minPath, functions, max); System.out.printf("%nWith functions: %s%n", functions); System.out.printf(" Minimum steps to 1:%n"); for ( int n = 2 ; n <= max ; n++ ) { int steps = minPath.get(n).size(); System.out.printf(" %2d: %d step%1s: %s%n", n, steps, steps == 1 ? "" : "s", minPath.get(n)); } displayMaxMin(minPath, functions, 2000); displayMaxMin(minPath, functions, 20000); displayMaxMin(minPath, functions, 100000); } private static void displayMaxMin(Map<Integer,List<String>> minPath, List<Function> functions, int max) { populateMap(minPath, functions, max); List<Integer> maxIntegers = getMaxMin(minPath, max); int maxSteps = maxIntegers.remove(0); int numCount = maxIntegers.size(); System.out.printf(" There %s %d number%s in the range 1-%d that have maximum 'minimal steps' of %d:%n %s%n", numCount == 1 ? "is" : "are", numCount, numCount == 1 ? "" : "s", max, maxSteps, maxIntegers); } private static List<Integer> getMaxMin(Map<Integer,List<String>> minPath, int max) { int maxSteps = Integer.MIN_VALUE; List<Integer> maxIntegers = new ArrayList<Integer>(); for ( int n = 2 ; n <= max ; n++ ) { int len = minPath.get(n).size(); if ( len > maxSteps ) { maxSteps = len; maxIntegers.clear(); maxIntegers.add(n); } else if ( len == maxSteps ) { maxIntegers.add(n); } } maxIntegers.add(0, maxSteps); return maxIntegers; } private static void populateMap(Map<Integer,List<String>> minPath, List<Function> functions, int max) { for ( int n = 2 ; n <= max ; n++ ) { if ( minPath.containsKey(n) ) { continue; } Function minFunction = null; int minSteps = Integer.MAX_VALUE; for ( Function f : functions ) { if ( f.actionOk(n) ) { int result = f.action(n); int steps = 1 + minPath.get(result).size(); if ( steps < minSteps ) { minFunction = f; minSteps = steps; } } } int result = minFunction.action(n); List<String> path = new ArrayList<String>(); path.add(minFunction.toString(n)); path.addAll(minPath.get(result)); minPath.put(n, path); } } private static Map<Integer,List<String>> getInitialMap(List<Function> functions, int max) { Map<Integer,List<String>> minPath = new HashMap<>(); for ( int i = 2 ; i <= max ; i++ ) { for ( Function f : functions ) { if ( f.actionOk(i) ) { int result = f.action(i); if ( result == 1 ) { List<String> path = new ArrayList<String>(); path.add(f.toString(i)); minPath.put(i, path); } } } } return minPath; } private static List<Function> getFunctions3() { List<Function> functions = new ArrayList<>(); functions.add(new Divide2Function()); functions.add(new Divide3Function()); functions.add(new Subtract2Function()); functions.add(new Subtract1Function()); return functions; } private static List<Function> getFunctions2() { List<Function> functions = new ArrayList<>(); functions.add(new Divide3Function()); functions.add(new Divide2Function()); functions.add(new Subtract2Function()); return functions; } private static List<Function> getFunctions1() { List<Function> functions = new ArrayList<>(); functions.add(new Divide3Function()); functions.add(new Divide2Function()); functions.add(new Subtract1Function()); return functions; } public abstract static class Function { abstract public int action(int n); abstract public boolean actionOk(int n); abstract public String toString(int n); } public static class Divide2Function extends Function { @Override public int action(int n) { return n/2; } @Override public boolean actionOk(int n) { return n % 2 == 0; } @Override public String toString(int n) { return "/2 -> " + n/2; } @Override public String toString() { return "Divisor 2"; } } public static class Divide3Function extends Function { @Override public int action(int n) { return n/3; } @Override public boolean actionOk(int n) { return n % 3 == 0; } @Override public String toString(int n) { return "/3 -> " + n/3; } @Override public String toString() { return "Divisor 3"; } } public static class Subtract1Function extends Function { @Override public int action(int n) { return n-1; } @Override public boolean actionOk(int n) { return true; } @Override public String toString(int n) { return "-1 -> " + (n-1); } @Override public String toString() { return "Subtractor 1"; } } public static class Subtract2Function extends Function { @Override public int action(int n) { return n-2; } @Override public boolean actionOk(int n) { return n > 2; } @Override public String toString(int n) { return "-2 -> " + (n-2); } @Override public String toString() { return "Subtractor 2"; } } }
Port the following code from Go to Java with equivalent syntax and logic.
package main import ( "fmt" "strings" ) const text = `Given$a$text$file$of$many$lines,$where$fields$within$a$line$ are$delineated$by$a$single$'dollar'$character,$write$a$program that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$ column$are$separated$by$at$least$one$space. Further,$allow$for$each$word$in$a$column$to$be$either$left$ justified,$right$justified,$or$center$justified$within$its$column.` type formatter struct { text [][]string width []int } func newFormatter(text string) *formatter { var f formatter for _, line := range strings.Split(text, "\n") { words := strings.Split(line, "$") for words[len(words)-1] == "" { words = words[:len(words)-1] } f.text = append(f.text, words) for i, word := range words { if i == len(f.width) { f.width = append(f.width, len(word)) } else if len(word) > f.width[i] { f.width[i] = len(word) } } } return &f } const ( left = iota middle right ) func (f formatter) print(j int) { for _, line := range f.text { for i, word := range line { fmt.Printf("%-*s ", f.width[i], fmt.Sprintf("%*s", len(word)+(f.width[i]-len(word))*j/2, word)) } fmt.Println("") } fmt.Println("") } func main() { f := newFormatter(text) f.print(left) f.print(middle) f.print(right) }
import java.io.IOException; import java.nio.charset.StandardCharsets; import java.nio.file.Files; import java.nio.file.Paths; import java.util.ArrayList; import java.util.List; import org.apache.commons.lang3.StringUtils; public class ColumnAligner { private List<String[]> words = new ArrayList<>(); private int columns = 0; private List<Integer> columnWidths = new ArrayList<>(); public ColumnAligner(String s) { String[] lines = s.split("\\n"); for (String line : lines) { processInputLine(line); } } public ColumnAligner(List<String> lines) { for (String line : lines) { processInputLine(line); } } private void processInputLine(String line) { String[] lineWords = line.split("\\$"); words.add(lineWords); columns = Math.max(columns, lineWords.length); for (int i = 0; i < lineWords.length; i++) { String word = lineWords[i]; if (i >= columnWidths.size()) { columnWidths.add(word.length()); } else { columnWidths.set(i, Math.max(columnWidths.get(i), word.length())); } } } interface AlignFunction { String align(String s, int length); } public String alignLeft() { return align(new AlignFunction() { @Override public String align(String s, int length) { return StringUtils.rightPad(s, length); } }); } public String alignRight() { return align(new AlignFunction() { @Override public String align(String s, int length) { return StringUtils.leftPad(s, length); } }); } public String alignCenter() { return align(new AlignFunction() { @Override public String align(String s, int length) { return StringUtils.center(s, length); } }); } private String align(AlignFunction a) { StringBuilder result = new StringBuilder(); for (String[] lineWords : words) { for (int i = 0; i < lineWords.length; i++) { String word = lineWords[i]; if (i == 0) { result.append("|"); } result.append(a.align(word, columnWidths.get(i)) + "|"); } result.append("\n"); } return result.toString(); } public static void main(String args[]) throws IOException { if (args.length < 1) { System.out.println("Usage: ColumnAligner file [left|right|center]"); return; } String filePath = args[0]; String alignment = "left"; if (args.length >= 2) { alignment = args[1]; } ColumnAligner ca = new ColumnAligner(Files.readAllLines(Paths.get(filePath), StandardCharsets.UTF_8)); switch (alignment) { case "left": System.out.print(ca.alignLeft()); break; case "right": System.out.print(ca.alignRight()); break; case "center": System.out.print(ca.alignCenter()); break; default: System.err.println(String.format("Error! Unknown alignment: '%s'", alignment)); break; } } }
Translate this program into Java but keep the logic exactly as in Go.
package main import ( "fmt" "log" "net" "net/url" ) func main() { for _, in := range []string{ "foo: "urn:example:animal:ferret:nose", "jdbc:mysql: "ftp: "http: "ldap: "mailto:John.Doe@example.com", "news:comp.infosystems.www.servers.unix", "tel:+1-816-555-1212", "telnet: "urn:oasis:names:specification:docbook:dtd:xml:4.1.2", "ssh: "https: "http: } { fmt.Println(in) u, err := url.Parse(in) if err != nil { log.Println(err) continue } if in != u.String() { fmt.Printf("Note: reassmebles as %q\n", u) } printURL(u) } } func printURL(u *url.URL) { fmt.Println(" Scheme:", u.Scheme) if u.Opaque != "" { fmt.Println(" Opaque:", u.Opaque) } if u.User != nil { fmt.Println(" Username:", u.User.Username()) if pwd, ok := u.User.Password(); ok { fmt.Println(" Password:", pwd) } } if u.Host != "" { if host, port, err := net.SplitHostPort(u.Host); err == nil { fmt.Println(" Host:", host) fmt.Println(" Port:", port) } else { fmt.Println(" Host:", u.Host) } } if u.Path != "" { fmt.Println(" Path:", u.Path) } if u.RawQuery != "" { fmt.Println(" RawQuery:", u.RawQuery) m, err := url.ParseQuery(u.RawQuery) if err == nil { for k, v := range m { fmt.Printf(" Key: %q Values: %q\n", k, v) } } } if u.Fragment != "" { fmt.Println(" Fragment:", u.Fragment) } }
import java.net.URI; import java.net.URISyntaxException; public class WebAddressParser{ public static void main(String[] args){ parseAddress("foo: parseAddress("urn:example:animal:ferret:nose"); } static void parseAddress(String a){ System.out.println("Parsing " + a); try{ URI u = new URI(a); System.out.println("\tscheme = " + u.getScheme()); System.out.println("\tdomain = " + u.getHost()); System.out.println("\tport = " + (-1==u.getPort()?"default":u.getPort())); System.out.println("\tpath = " + (null==u.getPath()?u.getSchemeSpecificPart():u.getPath())); System.out.println("\tquery = " + u.getQuery()); System.out.println("\tfragment = " + u.getFragment()); } catch (URISyntaxException x){ System.err.println("Oops: " + x); } } }
Ensure the translated Java code behaves exactly like the original Go snippet.
package main import ( "fmt" "log" "net" "net/url" ) func main() { for _, in := range []string{ "foo: "urn:example:animal:ferret:nose", "jdbc:mysql: "ftp: "http: "ldap: "mailto:John.Doe@example.com", "news:comp.infosystems.www.servers.unix", "tel:+1-816-555-1212", "telnet: "urn:oasis:names:specification:docbook:dtd:xml:4.1.2", "ssh: "https: "http: } { fmt.Println(in) u, err := url.Parse(in) if err != nil { log.Println(err) continue } if in != u.String() { fmt.Printf("Note: reassmebles as %q\n", u) } printURL(u) } } func printURL(u *url.URL) { fmt.Println(" Scheme:", u.Scheme) if u.Opaque != "" { fmt.Println(" Opaque:", u.Opaque) } if u.User != nil { fmt.Println(" Username:", u.User.Username()) if pwd, ok := u.User.Password(); ok { fmt.Println(" Password:", pwd) } } if u.Host != "" { if host, port, err := net.SplitHostPort(u.Host); err == nil { fmt.Println(" Host:", host) fmt.Println(" Port:", port) } else { fmt.Println(" Host:", u.Host) } } if u.Path != "" { fmt.Println(" Path:", u.Path) } if u.RawQuery != "" { fmt.Println(" RawQuery:", u.RawQuery) m, err := url.ParseQuery(u.RawQuery) if err == nil { for k, v := range m { fmt.Printf(" Key: %q Values: %q\n", k, v) } } } if u.Fragment != "" { fmt.Println(" Fragment:", u.Fragment) } }
import java.net.URI; import java.net.URISyntaxException; public class WebAddressParser{ public static void main(String[] args){ parseAddress("foo: parseAddress("urn:example:animal:ferret:nose"); } static void parseAddress(String a){ System.out.println("Parsing " + a); try{ URI u = new URI(a); System.out.println("\tscheme = " + u.getScheme()); System.out.println("\tdomain = " + u.getHost()); System.out.println("\tport = " + (-1==u.getPort()?"default":u.getPort())); System.out.println("\tpath = " + (null==u.getPath()?u.getSchemeSpecificPart():u.getPath())); System.out.println("\tquery = " + u.getQuery()); System.out.println("\tfragment = " + u.getFragment()); } catch (URISyntaxException x){ System.err.println("Oops: " + x); } } }
Convert this Go block to Java, preserving its control flow and logic.
package main import ( "fmt" "log" "math/big" "strings" ) const alphabet = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz" var big0 = new(big.Int) var big58 = big.NewInt(58) func reverse(s string) string { r := []rune(s) for i, j := 0, len(r)-1; i < len(r)/2; i, j = i+1, j-1 { r[i], r[j] = r[j], r[i] } return string(r) } func convertToBase58(hash string, base int) (string, error) { var x, ok = new(big.Int).SetString(hash, base) if !ok { return "", fmt.Errorf("'%v' is not a valid integer in base '%d'", hash, base) } var sb strings.Builder var rem = new(big.Int) for x.Cmp(big0) == 1 { x.QuoRem(x, big58, rem) r := rem.Int64() sb.WriteByte(alphabet[r]) } return reverse(sb.String()), nil } func main() { s := "25420294593250030202636073700053352635053786165627414518" b, err := convertToBase58(s, 10) if err != nil { log.Fatal(err) } fmt.Println(s, "->", b) hashes := [...]string{ "0x61", "0x626262", "0x636363", "0x73696d706c792061206c6f6e6720737472696e67", "0x516b6fcd0f", "0xbf4f89001e670274dd", "0x572e4794", "0xecac89cad93923c02321", "0x10c8511e", } for _, hash := range hashes { b58, err := convertToBase58(hash, 0) if err != nil { log.Fatal(err) } fmt.Printf("%-56s -> %s\n", hash, b58) } }
import java.math.BigInteger; import java.util.List; public class Base58CheckEncoding { private static final String ALPHABET = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"; private static final BigInteger BIG0 = BigInteger.ZERO; private static final BigInteger BIG58 = BigInteger.valueOf(58); private static String convertToBase58(String hash) { return convertToBase58(hash, 16); } private static String convertToBase58(String hash, int base) { BigInteger x; if (base == 16 && hash.substring(0, 2).equals("0x")) { x = new BigInteger(hash.substring(2), 16); } else { x = new BigInteger(hash, base); } StringBuilder sb = new StringBuilder(); while (x.compareTo(BIG0) > 0) { int r = x.mod(BIG58).intValue(); sb.append(ALPHABET.charAt(r)); x = x.divide(BIG58); } return sb.reverse().toString(); } public static void main(String[] args) { String s = "25420294593250030202636073700053352635053786165627414518"; String b = convertToBase58(s, 10); System.out.printf("%s -> %s\n", s, b); List<String> hashes = List.of( "0x61", "0x626262", "0x636363", "0x73696d706c792061206c6f6e6720737472696e67", "0x516b6fcd0f", "0xbf4f89001e670274dd", "0x572e4794", "0xecac89cad93923c02321", "0x10c8511e" ); for (String hash : hashes) { String b58 = convertToBase58(hash); System.out.printf("%-56s -> %s\n", hash, b58); } } }
Generate a Java translation of this Go snippet without changing its computational steps.
package main import ( "fmt" "log" "math/big" "strings" ) const alphabet = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz" var big0 = new(big.Int) var big58 = big.NewInt(58) func reverse(s string) string { r := []rune(s) for i, j := 0, len(r)-1; i < len(r)/2; i, j = i+1, j-1 { r[i], r[j] = r[j], r[i] } return string(r) } func convertToBase58(hash string, base int) (string, error) { var x, ok = new(big.Int).SetString(hash, base) if !ok { return "", fmt.Errorf("'%v' is not a valid integer in base '%d'", hash, base) } var sb strings.Builder var rem = new(big.Int) for x.Cmp(big0) == 1 { x.QuoRem(x, big58, rem) r := rem.Int64() sb.WriteByte(alphabet[r]) } return reverse(sb.String()), nil } func main() { s := "25420294593250030202636073700053352635053786165627414518" b, err := convertToBase58(s, 10) if err != nil { log.Fatal(err) } fmt.Println(s, "->", b) hashes := [...]string{ "0x61", "0x626262", "0x636363", "0x73696d706c792061206c6f6e6720737472696e67", "0x516b6fcd0f", "0xbf4f89001e670274dd", "0x572e4794", "0xecac89cad93923c02321", "0x10c8511e", } for _, hash := range hashes { b58, err := convertToBase58(hash, 0) if err != nil { log.Fatal(err) } fmt.Printf("%-56s -> %s\n", hash, b58) } }
import java.math.BigInteger; import java.util.List; public class Base58CheckEncoding { private static final String ALPHABET = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"; private static final BigInteger BIG0 = BigInteger.ZERO; private static final BigInteger BIG58 = BigInteger.valueOf(58); private static String convertToBase58(String hash) { return convertToBase58(hash, 16); } private static String convertToBase58(String hash, int base) { BigInteger x; if (base == 16 && hash.substring(0, 2).equals("0x")) { x = new BigInteger(hash.substring(2), 16); } else { x = new BigInteger(hash, base); } StringBuilder sb = new StringBuilder(); while (x.compareTo(BIG0) > 0) { int r = x.mod(BIG58).intValue(); sb.append(ALPHABET.charAt(r)); x = x.divide(BIG58); } return sb.reverse().toString(); } public static void main(String[] args) { String s = "25420294593250030202636073700053352635053786165627414518"; String b = convertToBase58(s, 10); System.out.printf("%s -> %s\n", s, b); List<String> hashes = List.of( "0x61", "0x626262", "0x636363", "0x73696d706c792061206c6f6e6720737472696e67", "0x516b6fcd0f", "0xbf4f89001e670274dd", "0x572e4794", "0xecac89cad93923c02321", "0x10c8511e" ); for (String hash : hashes) { String b58 = convertToBase58(hash); System.out.printf("%-56s -> %s\n", hash, b58); } } }
Convert this Go snippet to Java and keep its semantics consistent.
package main import ( "bufio" "fmt" "log" "os" "strconv" "strings" ) func check(err error) { if err != nil { log.Fatal(err) } } func main() { scanner := bufio.NewScanner(os.Stdin) n := 0 for n < 1 || n > 5 { fmt.Print("How many integer variables do you want to create (max 5) : ") scanner.Scan() n, _ = strconv.Atoi(scanner.Text()) check(scanner.Err()) } vars := make(map[string]int) fmt.Println("OK, enter the variable names and their values, below") for i := 1; i <= n; { fmt.Println("\n Variable", i) fmt.Print(" Name  : ") scanner.Scan() name := scanner.Text() check(scanner.Err()) if _, ok := vars[name]; ok { fmt.Println(" Sorry, you've already created a variable of that name, try again") continue } var value int var err error for { fmt.Print(" Value : ") scanner.Scan() value, err = strconv.Atoi(scanner.Text()) check(scanner.Err()) if err != nil { fmt.Println(" Not a valid integer, try again") } else { break } } vars[name] = value i++ } fmt.Println("\nEnter q to quit") for { fmt.Print("\nWhich variable do you want to inspect : ") scanner.Scan() name := scanner.Text() check(scanner.Err()) if s := strings.ToLower(name); s == "q" { return } v, ok := vars[name] if !ok { fmt.Println("Sorry there's no variable of that name, try again") } else { fmt.Println("It's value is", v) } } }
public static void main(String... args){ HashMap<String, Integer> vars = new HashMap<String, Integer>(); vars.put("Variable name", 3); vars.put("Next variable name", 5); Scanner sc = new Scanner(System.in); String str = sc.next(); vars.put(str, sc.nextInt()); System.out.println(vars.get("Variable name")); System.out.println(vars.get(str)); }
Port the following code from Go to Java with equivalent syntax and logic.
package main import ( "bufio" "fmt" "log" "os" "strconv" "strings" ) func check(err error) { if err != nil { log.Fatal(err) } } func main() { scanner := bufio.NewScanner(os.Stdin) n := 0 for n < 1 || n > 5 { fmt.Print("How many integer variables do you want to create (max 5) : ") scanner.Scan() n, _ = strconv.Atoi(scanner.Text()) check(scanner.Err()) } vars := make(map[string]int) fmt.Println("OK, enter the variable names and their values, below") for i := 1; i <= n; { fmt.Println("\n Variable", i) fmt.Print(" Name  : ") scanner.Scan() name := scanner.Text() check(scanner.Err()) if _, ok := vars[name]; ok { fmt.Println(" Sorry, you've already created a variable of that name, try again") continue } var value int var err error for { fmt.Print(" Value : ") scanner.Scan() value, err = strconv.Atoi(scanner.Text()) check(scanner.Err()) if err != nil { fmt.Println(" Not a valid integer, try again") } else { break } } vars[name] = value i++ } fmt.Println("\nEnter q to quit") for { fmt.Print("\nWhich variable do you want to inspect : ") scanner.Scan() name := scanner.Text() check(scanner.Err()) if s := strings.ToLower(name); s == "q" { return } v, ok := vars[name] if !ok { fmt.Println("Sorry there's no variable of that name, try again") } else { fmt.Println("It's value is", v) } } }
public static void main(String... args){ HashMap<String, Integer> vars = new HashMap<String, Integer>(); vars.put("Variable name", 3); vars.put("Next variable name", 5); Scanner sc = new Scanner(System.in); String str = sc.next(); vars.put(str, sc.nextInt()); System.out.println(vars.get("Variable name")); System.out.println(vars.get(str)); }
Translate this program into Java but keep the logic exactly as in Go.
package main import ( "crypto/des" "encoding/hex" "fmt" "log" ) func main() { key, err := hex.DecodeString("0e329232ea6d0d73") if err != nil { log.Fatal(err) } c, err := des.NewCipher(key) if err != nil { log.Fatal(err) } src, err := hex.DecodeString("8787878787878787") if err != nil { log.Fatal(err) } dst := make([]byte, des.BlockSize) c.Encrypt(dst, src) fmt.Printf("%x\n", dst) }
import javax.crypto.Cipher; import javax.crypto.spec.SecretKeySpec; public class DataEncryptionStandard { private static byte[] toHexByteArray(String self) { byte[] bytes = new byte[self.length() / 2]; for (int i = 0; i < bytes.length; ++i) { bytes[i] = ((byte) Integer.parseInt(self.substring(i * 2, i * 2 + 2), 16)); } return bytes; } private static void printHexBytes(byte[] self, String label) { System.out.printf("%s: ", label); for (byte b : self) { int bb = (b >= 0) ? ((int) b) : b + 256; String ts = Integer.toString(bb, 16); if (ts.length() < 2) { ts = "0" + ts; } System.out.print(ts); } System.out.println(); } public static void main(String[] args) throws Exception { String strKey = "0e329232ea6d0d73"; byte[] keyBytes = toHexByteArray(strKey); SecretKeySpec key = new SecretKeySpec(keyBytes, "DES"); Cipher encCipher = Cipher.getInstance("DES"); encCipher.init(Cipher.ENCRYPT_MODE, key); String strPlain = "8787878787878787"; byte[] plainBytes = toHexByteArray(strPlain); byte[] encBytes = encCipher.doFinal(plainBytes); printHexBytes(encBytes, "Encoded"); Cipher decCipher = Cipher.getInstance("DES"); decCipher.init(Cipher.DECRYPT_MODE, key); byte[] decBytes = decCipher.doFinal(encBytes); printHexBytes(decBytes, "Decoded"); } }
Please provide an equivalent version of this Go code in Java.
package main import ( "fmt" big "github.com/ncw/gmp" "time" ) type vector = []*big.Int type matrix []vector var ( zero = new(big.Int) one = big.NewInt(1) ) func (m1 matrix) mul(m2 matrix) matrix { rows1, cols1 := len(m1), len(m1[0]) rows2, cols2 := len(m2), len(m2[0]) if cols1 != rows2 { panic("Matrices cannot be multiplied.") } result := make(matrix, rows1) temp := new(big.Int) for i := 0; i < rows1; i++ { result[i] = make(vector, cols2) for j := 0; j < cols2; j++ { result[i][j] = new(big.Int) for k := 0; k < rows2; k++ { temp.Mul(m1[i][k], m2[k][j]) result[i][j].Add(result[i][j], temp) } } } return result } func identityMatrix(n uint64) matrix { if n < 1 { panic("Size of identity matrix can't be less than 1") } ident := make(matrix, n) for i := uint64(0); i < n; i++ { ident[i] = make(vector, n) for j := uint64(0); j < n; j++ { ident[i][j] = new(big.Int) if i == j { ident[i][j].Set(one) } } } return ident } func (m matrix) pow(n *big.Int) matrix { le := len(m) if le != len(m[0]) { panic("Not a square matrix") } switch { case n.Cmp(zero) == -1: panic("Negative exponents not supported") case n.Cmp(zero) == 0: return identityMatrix(uint64(le)) case n.Cmp(one) == 0: return m } pow := identityMatrix(uint64(le)) base := m e := new(big.Int).Set(n) temp := new(big.Int) for e.Cmp(zero) > 0 { temp.And(e, one) if temp.Cmp(one) == 0 { pow = pow.mul(base) } e.Rsh(e, 1) base = base.mul(base) } return pow } func fibonacci(n *big.Int) *big.Int { if n.Cmp(zero) == 0 { return zero } m := matrix{{one, one}, {one, zero}} m = m.pow(n.Sub(n, one)) return m[0][0] } func commatize(n uint64) string { s := fmt.Sprintf("%d", n) le := len(s) for i := le - 3; i >= 1; i -= 3 { s = s[0:i] + "," + s[i:] } return s } func main() { start := time.Now() n := new(big.Int) for i := uint64(10); i <= 1e7; i *= 10 { n.SetUint64(i) s := fibonacci(n).String() fmt.Printf("The digits of the %sth Fibonacci number (%s) are:\n", commatize(i), commatize(uint64(len(s)))) if len(s) > 20 { fmt.Printf(" First 20 : %s\n", s[0:20]) if len(s) < 40 { fmt.Printf(" Final %-2d : %s\n", len(s)-20, s[20:]) } else { fmt.Printf(" Final 20 : %s\n", s[len(s)-20:]) } } else { fmt.Printf(" All %-2d  : %s\n", len(s), s) } fmt.Println() } sfxs := []string{"nd", "th"} for i, e := range []uint{16, 32} { n.Lsh(one, e) s := fibonacci(n).String() fmt.Printf("The digits of the 2^%d%s Fibonacci number (%s) are:\n", e, sfxs[i], commatize(uint64(len(s)))) fmt.Printf(" First 20 : %s\n", s[0:20]) fmt.Printf(" Final 20 : %s\n", s[len(s)-20:]) fmt.Println() } fmt.Printf("Took %s\n\n", time.Since(start)) }
import java.math.BigInteger; import java.util.Arrays; public class FibonacciMatrixExponentiation { public static void main(String[] args) { BigInteger mod = BigInteger.TEN.pow(20); for ( int exp : Arrays.asList(32, 64) ) { System.out.printf("Last 20 digits of fib(2^%d) = %s%n", exp, fibMod(BigInteger.valueOf(2).pow(exp), mod)); } for ( int i = 1 ; i <= 7 ; i++ ) { BigInteger n = BigInteger.TEN.pow(i); System.out.printf("fib(%,d) = %s%n", n, displayFib(fib(n))); } } private static String displayFib(BigInteger fib) { String s = fib.toString(); if ( s.length() <= 40 ) { return s; } return s.substring(0, 20) + " ... " + s.subSequence(s.length()-20, s.length()); } private static BigInteger fib(BigInteger k) { BigInteger aRes = BigInteger.ZERO; BigInteger bRes = BigInteger.ONE; BigInteger cRes = BigInteger.ONE; BigInteger aBase = BigInteger.ZERO; BigInteger bBase = BigInteger.ONE; BigInteger cBase = BigInteger.ONE; while ( k.compareTo(BigInteger.ZERO) > 0 ) { if ( k.mod(BigInteger.valueOf(2)).compareTo(BigInteger.ONE) == 0 ) { BigInteger temp1 = aRes.multiply(aBase).add(bRes.multiply(bBase)); BigInteger temp2 = aBase.multiply(bRes).add(bBase.multiply(cRes)); BigInteger temp3 = bBase.multiply(bRes).add(cBase.multiply(cRes)); aRes = temp1; bRes = temp2; cRes = temp3; } k = k.shiftRight(1); BigInteger temp1 = aBase.multiply(aBase).add(bBase.multiply(bBase)); BigInteger temp2 = aBase.multiply(bBase).add(bBase.multiply(cBase)); BigInteger temp3 = bBase.multiply(bBase).add(cBase.multiply(cBase)); aBase = temp1; bBase = temp2; cBase = temp3; } return aRes; } private static BigInteger fibMod(BigInteger k, BigInteger mod) { BigInteger aRes = BigInteger.ZERO; BigInteger bRes = BigInteger.ONE; BigInteger cRes = BigInteger.ONE; BigInteger aBase = BigInteger.ZERO; BigInteger bBase = BigInteger.ONE; BigInteger cBase = BigInteger.ONE; while ( k.compareTo(BigInteger.ZERO) > 0 ) { if ( k.mod(BigInteger.valueOf(2)).compareTo(BigInteger.ONE) == 0 ) { BigInteger temp1 = aRes.multiply(aBase).add(bRes.multiply(bBase)).mod(mod); BigInteger temp2 = aBase.multiply(bRes).add(bBase.multiply(cRes)).mod(mod); BigInteger temp3 = bBase.multiply(bRes).add(cBase.multiply(cRes)).mod(mod); aRes = temp1; bRes = temp2; cRes = temp3; } k = k.shiftRight(1); BigInteger temp1 = aBase.multiply(aBase).add(bBase.multiply(bBase)).mod(mod); BigInteger temp2 = aBase.multiply(bBase).add(bBase.multiply(cBase)).mod(mod); BigInteger temp3 = bBase.multiply(bBase).add(cBase.multiply(cBase)).mod(mod); aBase = temp1; bBase = temp2; cBase = temp3; } return aRes.mod(mod); } }
Change the following Go code into Java without altering its purpose.
package main import ( "fmt" big "github.com/ncw/gmp" "time" ) type vector = []*big.Int type matrix []vector var ( zero = new(big.Int) one = big.NewInt(1) ) func (m1 matrix) mul(m2 matrix) matrix { rows1, cols1 := len(m1), len(m1[0]) rows2, cols2 := len(m2), len(m2[0]) if cols1 != rows2 { panic("Matrices cannot be multiplied.") } result := make(matrix, rows1) temp := new(big.Int) for i := 0; i < rows1; i++ { result[i] = make(vector, cols2) for j := 0; j < cols2; j++ { result[i][j] = new(big.Int) for k := 0; k < rows2; k++ { temp.Mul(m1[i][k], m2[k][j]) result[i][j].Add(result[i][j], temp) } } } return result } func identityMatrix(n uint64) matrix { if n < 1 { panic("Size of identity matrix can't be less than 1") } ident := make(matrix, n) for i := uint64(0); i < n; i++ { ident[i] = make(vector, n) for j := uint64(0); j < n; j++ { ident[i][j] = new(big.Int) if i == j { ident[i][j].Set(one) } } } return ident } func (m matrix) pow(n *big.Int) matrix { le := len(m) if le != len(m[0]) { panic("Not a square matrix") } switch { case n.Cmp(zero) == -1: panic("Negative exponents not supported") case n.Cmp(zero) == 0: return identityMatrix(uint64(le)) case n.Cmp(one) == 0: return m } pow := identityMatrix(uint64(le)) base := m e := new(big.Int).Set(n) temp := new(big.Int) for e.Cmp(zero) > 0 { temp.And(e, one) if temp.Cmp(one) == 0 { pow = pow.mul(base) } e.Rsh(e, 1) base = base.mul(base) } return pow } func fibonacci(n *big.Int) *big.Int { if n.Cmp(zero) == 0 { return zero } m := matrix{{one, one}, {one, zero}} m = m.pow(n.Sub(n, one)) return m[0][0] } func commatize(n uint64) string { s := fmt.Sprintf("%d", n) le := len(s) for i := le - 3; i >= 1; i -= 3 { s = s[0:i] + "," + s[i:] } return s } func main() { start := time.Now() n := new(big.Int) for i := uint64(10); i <= 1e7; i *= 10 { n.SetUint64(i) s := fibonacci(n).String() fmt.Printf("The digits of the %sth Fibonacci number (%s) are:\n", commatize(i), commatize(uint64(len(s)))) if len(s) > 20 { fmt.Printf(" First 20 : %s\n", s[0:20]) if len(s) < 40 { fmt.Printf(" Final %-2d : %s\n", len(s)-20, s[20:]) } else { fmt.Printf(" Final 20 : %s\n", s[len(s)-20:]) } } else { fmt.Printf(" All %-2d  : %s\n", len(s), s) } fmt.Println() } sfxs := []string{"nd", "th"} for i, e := range []uint{16, 32} { n.Lsh(one, e) s := fibonacci(n).String() fmt.Printf("The digits of the 2^%d%s Fibonacci number (%s) are:\n", e, sfxs[i], commatize(uint64(len(s)))) fmt.Printf(" First 20 : %s\n", s[0:20]) fmt.Printf(" Final 20 : %s\n", s[len(s)-20:]) fmt.Println() } fmt.Printf("Took %s\n\n", time.Since(start)) }
import java.math.BigInteger; import java.util.Arrays; public class FibonacciMatrixExponentiation { public static void main(String[] args) { BigInteger mod = BigInteger.TEN.pow(20); for ( int exp : Arrays.asList(32, 64) ) { System.out.printf("Last 20 digits of fib(2^%d) = %s%n", exp, fibMod(BigInteger.valueOf(2).pow(exp), mod)); } for ( int i = 1 ; i <= 7 ; i++ ) { BigInteger n = BigInteger.TEN.pow(i); System.out.printf("fib(%,d) = %s%n", n, displayFib(fib(n))); } } private static String displayFib(BigInteger fib) { String s = fib.toString(); if ( s.length() <= 40 ) { return s; } return s.substring(0, 20) + " ... " + s.subSequence(s.length()-20, s.length()); } private static BigInteger fib(BigInteger k) { BigInteger aRes = BigInteger.ZERO; BigInteger bRes = BigInteger.ONE; BigInteger cRes = BigInteger.ONE; BigInteger aBase = BigInteger.ZERO; BigInteger bBase = BigInteger.ONE; BigInteger cBase = BigInteger.ONE; while ( k.compareTo(BigInteger.ZERO) > 0 ) { if ( k.mod(BigInteger.valueOf(2)).compareTo(BigInteger.ONE) == 0 ) { BigInteger temp1 = aRes.multiply(aBase).add(bRes.multiply(bBase)); BigInteger temp2 = aBase.multiply(bRes).add(bBase.multiply(cRes)); BigInteger temp3 = bBase.multiply(bRes).add(cBase.multiply(cRes)); aRes = temp1; bRes = temp2; cRes = temp3; } k = k.shiftRight(1); BigInteger temp1 = aBase.multiply(aBase).add(bBase.multiply(bBase)); BigInteger temp2 = aBase.multiply(bBase).add(bBase.multiply(cBase)); BigInteger temp3 = bBase.multiply(bBase).add(cBase.multiply(cBase)); aBase = temp1; bBase = temp2; cBase = temp3; } return aRes; } private static BigInteger fibMod(BigInteger k, BigInteger mod) { BigInteger aRes = BigInteger.ZERO; BigInteger bRes = BigInteger.ONE; BigInteger cRes = BigInteger.ONE; BigInteger aBase = BigInteger.ZERO; BigInteger bBase = BigInteger.ONE; BigInteger cBase = BigInteger.ONE; while ( k.compareTo(BigInteger.ZERO) > 0 ) { if ( k.mod(BigInteger.valueOf(2)).compareTo(BigInteger.ONE) == 0 ) { BigInteger temp1 = aRes.multiply(aBase).add(bRes.multiply(bBase)).mod(mod); BigInteger temp2 = aBase.multiply(bRes).add(bBase.multiply(cRes)).mod(mod); BigInteger temp3 = bBase.multiply(bRes).add(cBase.multiply(cRes)).mod(mod); aRes = temp1; bRes = temp2; cRes = temp3; } k = k.shiftRight(1); BigInteger temp1 = aBase.multiply(aBase).add(bBase.multiply(bBase)).mod(mod); BigInteger temp2 = aBase.multiply(bBase).add(bBase.multiply(cBase)).mod(mod); BigInteger temp3 = bBase.multiply(bBase).add(cBase.multiply(cBase)).mod(mod); aBase = temp1; bBase = temp2; cBase = temp3; } return aRes.mod(mod); } }
Ensure the translated Java code behaves exactly like the original Go snippet.
package main import ( "fmt" big "github.com/ncw/gmp" "time" ) type vector = []*big.Int type matrix []vector var ( zero = new(big.Int) one = big.NewInt(1) ) func (m1 matrix) mul(m2 matrix) matrix { rows1, cols1 := len(m1), len(m1[0]) rows2, cols2 := len(m2), len(m2[0]) if cols1 != rows2 { panic("Matrices cannot be multiplied.") } result := make(matrix, rows1) temp := new(big.Int) for i := 0; i < rows1; i++ { result[i] = make(vector, cols2) for j := 0; j < cols2; j++ { result[i][j] = new(big.Int) for k := 0; k < rows2; k++ { temp.Mul(m1[i][k], m2[k][j]) result[i][j].Add(result[i][j], temp) } } } return result } func identityMatrix(n uint64) matrix { if n < 1 { panic("Size of identity matrix can't be less than 1") } ident := make(matrix, n) for i := uint64(0); i < n; i++ { ident[i] = make(vector, n) for j := uint64(0); j < n; j++ { ident[i][j] = new(big.Int) if i == j { ident[i][j].Set(one) } } } return ident } func (m matrix) pow(n *big.Int) matrix { le := len(m) if le != len(m[0]) { panic("Not a square matrix") } switch { case n.Cmp(zero) == -1: panic("Negative exponents not supported") case n.Cmp(zero) == 0: return identityMatrix(uint64(le)) case n.Cmp(one) == 0: return m } pow := identityMatrix(uint64(le)) base := m e := new(big.Int).Set(n) temp := new(big.Int) for e.Cmp(zero) > 0 { temp.And(e, one) if temp.Cmp(one) == 0 { pow = pow.mul(base) } e.Rsh(e, 1) base = base.mul(base) } return pow } func fibonacci(n *big.Int) *big.Int { if n.Cmp(zero) == 0 { return zero } m := matrix{{one, one}, {one, zero}} m = m.pow(n.Sub(n, one)) return m[0][0] } func commatize(n uint64) string { s := fmt.Sprintf("%d", n) le := len(s) for i := le - 3; i >= 1; i -= 3 { s = s[0:i] + "," + s[i:] } return s } func main() { start := time.Now() n := new(big.Int) for i := uint64(10); i <= 1e7; i *= 10 { n.SetUint64(i) s := fibonacci(n).String() fmt.Printf("The digits of the %sth Fibonacci number (%s) are:\n", commatize(i), commatize(uint64(len(s)))) if len(s) > 20 { fmt.Printf(" First 20 : %s\n", s[0:20]) if len(s) < 40 { fmt.Printf(" Final %-2d : %s\n", len(s)-20, s[20:]) } else { fmt.Printf(" Final 20 : %s\n", s[len(s)-20:]) } } else { fmt.Printf(" All %-2d  : %s\n", len(s), s) } fmt.Println() } sfxs := []string{"nd", "th"} for i, e := range []uint{16, 32} { n.Lsh(one, e) s := fibonacci(n).String() fmt.Printf("The digits of the 2^%d%s Fibonacci number (%s) are:\n", e, sfxs[i], commatize(uint64(len(s)))) fmt.Printf(" First 20 : %s\n", s[0:20]) fmt.Printf(" Final 20 : %s\n", s[len(s)-20:]) fmt.Println() } fmt.Printf("Took %s\n\n", time.Since(start)) }
import java.math.BigInteger; import java.util.Arrays; public class FibonacciMatrixExponentiation { public static void main(String[] args) { BigInteger mod = BigInteger.TEN.pow(20); for ( int exp : Arrays.asList(32, 64) ) { System.out.printf("Last 20 digits of fib(2^%d) = %s%n", exp, fibMod(BigInteger.valueOf(2).pow(exp), mod)); } for ( int i = 1 ; i <= 7 ; i++ ) { BigInteger n = BigInteger.TEN.pow(i); System.out.printf("fib(%,d) = %s%n", n, displayFib(fib(n))); } } private static String displayFib(BigInteger fib) { String s = fib.toString(); if ( s.length() <= 40 ) { return s; } return s.substring(0, 20) + " ... " + s.subSequence(s.length()-20, s.length()); } private static BigInteger fib(BigInteger k) { BigInteger aRes = BigInteger.ZERO; BigInteger bRes = BigInteger.ONE; BigInteger cRes = BigInteger.ONE; BigInteger aBase = BigInteger.ZERO; BigInteger bBase = BigInteger.ONE; BigInteger cBase = BigInteger.ONE; while ( k.compareTo(BigInteger.ZERO) > 0 ) { if ( k.mod(BigInteger.valueOf(2)).compareTo(BigInteger.ONE) == 0 ) { BigInteger temp1 = aRes.multiply(aBase).add(bRes.multiply(bBase)); BigInteger temp2 = aBase.multiply(bRes).add(bBase.multiply(cRes)); BigInteger temp3 = bBase.multiply(bRes).add(cBase.multiply(cRes)); aRes = temp1; bRes = temp2; cRes = temp3; } k = k.shiftRight(1); BigInteger temp1 = aBase.multiply(aBase).add(bBase.multiply(bBase)); BigInteger temp2 = aBase.multiply(bBase).add(bBase.multiply(cBase)); BigInteger temp3 = bBase.multiply(bBase).add(cBase.multiply(cBase)); aBase = temp1; bBase = temp2; cBase = temp3; } return aRes; } private static BigInteger fibMod(BigInteger k, BigInteger mod) { BigInteger aRes = BigInteger.ZERO; BigInteger bRes = BigInteger.ONE; BigInteger cRes = BigInteger.ONE; BigInteger aBase = BigInteger.ZERO; BigInteger bBase = BigInteger.ONE; BigInteger cBase = BigInteger.ONE; while ( k.compareTo(BigInteger.ZERO) > 0 ) { if ( k.mod(BigInteger.valueOf(2)).compareTo(BigInteger.ONE) == 0 ) { BigInteger temp1 = aRes.multiply(aBase).add(bRes.multiply(bBase)).mod(mod); BigInteger temp2 = aBase.multiply(bRes).add(bBase.multiply(cRes)).mod(mod); BigInteger temp3 = bBase.multiply(bRes).add(cBase.multiply(cRes)).mod(mod); aRes = temp1; bRes = temp2; cRes = temp3; } k = k.shiftRight(1); BigInteger temp1 = aBase.multiply(aBase).add(bBase.multiply(bBase)).mod(mod); BigInteger temp2 = aBase.multiply(bBase).add(bBase.multiply(cBase)).mod(mod); BigInteger temp3 = bBase.multiply(bBase).add(cBase.multiply(cBase)).mod(mod); aBase = temp1; bBase = temp2; cBase = temp3; } return aRes.mod(mod); } }
Generate an equivalent Java version of this Go code.
package main import ( "fmt" "regexp" "strings" ) var reg = regexp.MustCompile(`(\.[0-9]+|[1-9]([0-9]+)?(\.[0-9]+)?)`) func reverse(s string) string { r := []rune(s) for i, j := 0, len(r)-1; i < len(r)/2; i, j = i+1, j-1 { r[i], r[j] = r[j], r[i] } return string(r) } func commatize(s string, startIndex, period int, sep string) string { if startIndex < 0 || startIndex >= len(s) || period < 1 || sep == "" { return s } m := reg.FindString(s[startIndex:]) if m == "" { return s } splits := strings.Split(m, ".") ip := splits[0] if len(ip) > period { pi := reverse(ip) for i := (len(ip) - 1) / period * period; i >= period; i -= period { pi = pi[:i] + sep + pi[i:] } ip = reverse(pi) } if strings.Contains(m, ".") { dp := splits[1] if len(dp) > period { for i := (len(dp) - 1) / period * period; i >= period; i -= period { dp = dp[:i] + sep + dp[i:] } } ip += "." + dp } return s[:startIndex] + strings.Replace(s[startIndex:], m, ip, 1) } func main() { tests := [...]string{ "123456789.123456789", ".123456789", "57256.1D-4", "pi=3.14159265358979323846264338327950288419716939937510582097494459231", "The author has two Z$100000000000000 Zimbabwe notes (100 trillion).", "-in Aus$+1411.8millions", "===US$0017440 millions=== (in 2000 dollars)", "123.e8000 is pretty big.", "The land area of the earth is 57268900(29% of the surface) square miles.", "Ain't no numbers in this here words, nohow, no way, Jose.", "James was never known as 0000000007", "Arthur Eddington wrote: I believe there are " + "15747724136275002577605653961181555468044717914527116709366231425076185631031296" + " protons in the universe.", " $-140000±100 millions.", "6/9/1946 was a good year for some.", } fmt.Println(commatize(tests[0], 0, 2, "*")) fmt.Println(commatize(tests[1], 0, 3, "-")) fmt.Println(commatize(tests[2], 0, 4, "__")) fmt.Println(commatize(tests[3], 0, 5, " ")) fmt.Println(commatize(tests[4], 0, 3, ".")) for _, test := range tests[5:] { fmt.Println(commatize(test, 0, 3, ",")) } }
import java.io.File; import java.util.*; import java.util.regex.*; public class CommatizingNumbers { public static void main(String[] args) throws Exception { commatize("pi=3.14159265358979323846264338327950288419716939937510582" + "097494459231", 6, 5, " "); commatize("The author has two Z$100000000000000 Zimbabwe notes (100 " + "trillion).", 0, 3, "."); try (Scanner sc = new Scanner(new File("input.txt"))) { while(sc.hasNext()) commatize(sc.nextLine()); } } static void commatize(String s) { commatize(s, 0, 3, ","); } static void commatize(String s, int start, int step, String ins) { if (start < 0 || start > s.length() || step < 1 || step > s.length()) return; Matcher m = Pattern.compile("([1-9][0-9]*)").matcher(s.substring(start)); StringBuffer result = new StringBuffer(s.substring(0, start)); if (m.find()) { StringBuilder sb = new StringBuilder(m.group(1)).reverse(); for (int i = step; i < sb.length(); i += step) sb.insert(i++, ins); m.appendReplacement(result, sb.reverse().toString()); } System.out.println(m.appendTail(result)); } }
Generate an equivalent Java version of this Go code.
package main import ( "fmt" "math/big" ) func cumulative_freq(freq map[byte]int64) map[byte]int64 { total := int64(0) cf := make(map[byte]int64) for i := 0; i < 256; i++ { b := byte(i) if v, ok := freq[b]; ok { cf[b] = total total += v } } return cf } func arithmethic_coding(str string, radix int64) (*big.Int, *big.Int, map[byte]int64) { chars := []byte(str) freq := make(map[byte]int64) for _, c := range chars { freq[c] += 1 } cf := cumulative_freq(freq) base := len(chars) L := big.NewInt(0) pf := big.NewInt(1) bigBase := big.NewInt(int64(base)) for _, c := range chars { x := big.NewInt(cf[c]) L.Mul(L, bigBase) L.Add(L, x.Mul(x, pf)) pf.Mul(pf, big.NewInt(freq[c])) } U := big.NewInt(0) U.Set(L) U.Add(U, pf) bigOne := big.NewInt(1) bigZero := big.NewInt(0) bigRadix := big.NewInt(radix) tmp := big.NewInt(0).Set(pf) powr := big.NewInt(0) for { tmp.Div(tmp, bigRadix) if tmp.Cmp(bigZero) == 0 { break } powr.Add(powr, bigOne) } diff := big.NewInt(0) diff.Sub(U, bigOne) diff.Div(diff, big.NewInt(0).Exp(bigRadix, powr, nil)) return diff, powr, freq } func arithmethic_decoding(num *big.Int, radix int64, pow *big.Int, freq map[byte]int64) string { powr := big.NewInt(radix) enc := big.NewInt(0).Set(num) enc.Mul(enc, powr.Exp(powr, pow, nil)) base := int64(0) for _, v := range freq { base += v } cf := cumulative_freq(freq) dict := make(map[int64]byte) for k, v := range cf { dict[v] = k } lchar := -1 for i := int64(0); i < base; i++ { if v, ok := dict[i]; ok { lchar = int(v) } else if lchar != -1 { dict[i] = byte(lchar) } } decoded := make([]byte, base) bigBase := big.NewInt(base) for i := base - 1; i >= 0; i-- { pow := big.NewInt(0) pow.Exp(bigBase, big.NewInt(i), nil) div := big.NewInt(0) div.Div(enc, pow) c := dict[div.Int64()] fv := freq[c] cv := cf[c] prod := big.NewInt(0).Mul(pow, big.NewInt(cv)) diff := big.NewInt(0).Sub(enc, prod) enc.Div(diff, big.NewInt(fv)) decoded[base-i-1] = c } return string(decoded) } func main() { var radix = int64(10) strSlice := []string{ `DABDDB`, `DABDDBBDDBA`, `ABRACADABRA`, `TOBEORNOTTOBEORTOBEORNOT`, } for _, str := range strSlice { enc, pow, freq := arithmethic_coding(str, radix) dec := arithmethic_decoding(enc, radix, pow, freq) fmt.Printf("%-25s=> %19s * %d^%s\n", str, enc, radix, pow) if str != dec { panic("\tHowever that is incorrect!") } } }
import java.math.BigInteger; import java.util.HashMap; import java.util.Map; import java.util.Objects; public class ArithmeticCoding { private static class Triple<A, B, C> { A a; B b; C c; Triple(A a, B b, C c) { this.a = a; this.b = b; this.c = c; } } private static class Freq extends HashMap<Character, Long> { } private static Freq cumulativeFreq(Freq freq) { long total = 0; Freq cf = new Freq(); for (int i = 0; i < 256; ++i) { char c = (char) i; Long v = freq.get(c); if (v != null) { cf.put(c, total); total += v; } } return cf; } private static Triple<BigInteger, Integer, Freq> arithmeticCoding(String str, Long radix) { char[] chars = str.toCharArray(); Freq freq = new Freq(); for (char c : chars) { if (!freq.containsKey(c)) freq.put(c, 1L); else freq.put(c, freq.get(c) + 1); } Freq cf = cumulativeFreq(freq); BigInteger base = BigInteger.valueOf(chars.length); BigInteger lower = BigInteger.ZERO; BigInteger pf = BigInteger.ONE; for (char c : chars) { BigInteger x = BigInteger.valueOf(cf.get(c)); lower = lower.multiply(base).add(x.multiply(pf)); pf = pf.multiply(BigInteger.valueOf(freq.get(c))); } BigInteger upper = lower.add(pf); int powr = 0; BigInteger bigRadix = BigInteger.valueOf(radix); while (true) { pf = pf.divide(bigRadix); if (pf.equals(BigInteger.ZERO)) break; powr++; } BigInteger diff = upper.subtract(BigInteger.ONE).divide(bigRadix.pow(powr)); return new Triple<>(diff, powr, freq); } private static String arithmeticDecoding(BigInteger num, long radix, int pwr, Freq freq) { BigInteger powr = BigInteger.valueOf(radix); BigInteger enc = num.multiply(powr.pow(pwr)); long base = 0; for (Long v : freq.values()) base += v; Freq cf = cumulativeFreq(freq); Map<Long, Character> dict = new HashMap<>(); for (Map.Entry<Character, Long> entry : cf.entrySet()) dict.put(entry.getValue(), entry.getKey()); long lchar = -1; for (long i = 0; i < base; ++i) { Character v = dict.get(i); if (v != null) { lchar = v; } else if (lchar != -1) { dict.put(i, (char) lchar); } } StringBuilder decoded = new StringBuilder((int) base); BigInteger bigBase = BigInteger.valueOf(base); for (long i = base - 1; i >= 0; --i) { BigInteger pow = bigBase.pow((int) i); BigInteger div = enc.divide(pow); Character c = dict.get(div.longValue()); BigInteger fv = BigInteger.valueOf(freq.get(c)); BigInteger cv = BigInteger.valueOf(cf.get(c)); BigInteger diff = enc.subtract(pow.multiply(cv)); enc = diff.divide(fv); decoded.append(c); } return decoded.toString(); } public static void main(String[] args) { long radix = 10; String[] strings = {"DABDDB", "DABDDBBDDBA", "ABRACADABRA", "TOBEORNOTTOBEORTOBEORNOT"}; String fmt = "%-25s=> %19s * %d^%s\n"; for (String str : strings) { Triple<BigInteger, Integer, Freq> encoded = arithmeticCoding(str, radix); String dec = arithmeticDecoding(encoded.a, radix, encoded.b, encoded.c); System.out.printf(fmt, str, encoded.a, radix, encoded.b); if (!Objects.equals(str, dec)) throw new RuntimeException("\tHowever that is incorrect!"); } } }
Write the same code in Java as shown below in Go.
package main import "fmt" var g = [][]int{ 0: {1}, 1: {2}, 2: {0}, 3: {1, 2, 4}, 4: {3, 5}, 5: {2, 6}, 6: {5}, 7: {4, 6, 7}, } func main() { fmt.Println(kosaraju(g)) } func kosaraju(g [][]int) []int { vis := make([]bool, len(g)) L := make([]int, len(g)) x := len(L) t := make([][]int, len(g)) var Visit func(int) Visit = func(u int) { if !vis[u] { vis[u] = true for _, v := range g[u] { Visit(v) t[v] = append(t[v], u) } x-- L[x] = u } } for u := range g { Visit(u) } c := make([]int, len(g)) var Assign func(int, int) Assign = func(u, root int) { if vis[u] { vis[u] = false c[u] = root for _, v := range t[u] { Assign(v, root) } } } for _, u := range L { Assign(u, u) } return c }
import java.util.ArrayList; import java.util.Arrays; import java.util.List; import java.util.concurrent.atomic.AtomicInteger; import java.util.function.BiConsumer; import java.util.function.IntConsumer; import java.util.stream.Collectors; public class Kosaraju { static class Recursive<I> { I func; } private static List<Integer> kosaraju(List<List<Integer>> g) { int size = g.size(); boolean[] vis = new boolean[size]; int[] l = new int[size]; AtomicInteger x = new AtomicInteger(size); List<List<Integer>> t = new ArrayList<>(); for (int i = 0; i < size; ++i) { t.add(new ArrayList<>()); } Recursive<IntConsumer> visit = new Recursive<>(); visit.func = (int u) -> { if (!vis[u]) { vis[u] = true; for (Integer v : g.get(u)) { visit.func.accept(v); t.get(v).add(u); } int xval = x.decrementAndGet(); l[xval] = u; } }; for (int i = 0; i < size; ++i) { visit.func.accept(i); } int[] c = new int[size]; Recursive<BiConsumer<Integer, Integer>> assign = new Recursive<>(); assign.func = (Integer u, Integer root) -> { if (vis[u]) { vis[u] = false; c[u] = root; for (Integer v : t.get(u)) { assign.func.accept(v, root); } } }; for (int u : l) { assign.func.accept(u, u); } return Arrays.stream(c).boxed().collect(Collectors.toList()); } public static void main(String[] args) { List<List<Integer>> g = new ArrayList<>(); for (int i = 0; i < 8; ++i) { g.add(new ArrayList<>()); } g.get(0).add(1); g.get(1).add(2); g.get(2).add(0); g.get(3).add(1); g.get(3).add(2); g.get(3).add(4); g.get(4).add(3); g.get(4).add(5); g.get(5).add(2); g.get(5).add(6); g.get(6).add(5); g.get(7).add(4); g.get(7).add(6); g.get(7).add(7); List<Integer> output = kosaraju(g); System.out.println(output); } }
Maintain the same structure and functionality when rewriting this code in Java.
package main import ( "fmt" "image" "reflect" ) type t int func (r t) Twice() t { return r * 2 } func (r t) Half() t { return r / 2 } func (r t) Less(r2 t) bool { return r < r2 } func (r t) privateMethod() {} func main() { report(t(0)) report(image.Point{}) } func report(x interface{}) { v := reflect.ValueOf(x) t := reflect.TypeOf(x) n := t.NumMethod() fmt.Printf("Type %v has %d exported methods:\n", t, n) const format = "%-6s %-46s %s\n" fmt.Printf(format, "Name", "Method expression", "Method value") for i := 0; i < n; i++ { fmt.Printf(format, t.Method(i).Name, t.Method(i).Func.Type(), v.Method(i).Type(), ) } fmt.Println() }
import java.lang.reflect.Method; public class ListMethods { public int examplePublicInstanceMethod(char c, double d) { return 42; } private boolean examplePrivateInstanceMethod(String s) { return true; } public static void main(String[] args) { Class clazz = ListMethods.class; System.out.println("All public methods (including inherited):"); for (Method m : clazz.getMethods()) { System.out.println(m); } System.out.println(); System.out.println("All declared methods (excluding inherited):"); for (Method m : clazz.getDeclaredMethods()) { System.out.println(m); } } }
Write the same code in Java as shown below in Go.
package main import ( "fmt" "reflect" ) type example struct{} func (example) Foo() int { return 42 } func main() { var e example m := reflect.ValueOf(e).MethodByName("Foo") r := m.Call(nil) fmt.Println(r[0].Int()) }
import java.lang.reflect.Method; class Example { public int foo(int x) { return 42 + x; } } public class Main { public static void main(String[] args) throws Exception { Object example = new Example(); String name = "foo"; Class<?> clazz = example.getClass(); Method meth = clazz.getMethod(name, int.class); Object result = meth.invoke(example, 5); System.out.println(result); } }
Write the same code in Java as shown below in Go.
package main import ( "fmt" "math" "math/rand" "time" ) type ff = func([]float64) float64 type parameters struct{ omega, phip, phig float64 } type state struct { iter int gbpos []float64 gbval float64 min []float64 max []float64 params parameters pos [][]float64 vel [][]float64 bpos [][]float64 bval []float64 nParticles int nDims int } func (s state) report(testfunc string) { fmt.Println("Test Function  :", testfunc) fmt.Println("Iterations  :", s.iter) fmt.Println("Global Best Position :", s.gbpos) fmt.Println("Global Best Value  :", s.gbval) } func psoInit(min, max []float64, params parameters, nParticles int) *state { nDims := len(min) pos := make([][]float64, nParticles) vel := make([][]float64, nParticles) bpos := make([][]float64, nParticles) bval := make([]float64, nParticles) for i := 0; i < nParticles; i++ { pos[i] = min vel[i] = make([]float64, nDims) bpos[i] = min bval[i] = math.Inf(1) } iter := 0 gbpos := make([]float64, nDims) for i := 0; i < nDims; i++ { gbpos[i] = math.Inf(1) } gbval := math.Inf(1) return &state{iter, gbpos, gbval, min, max, params, pos, vel, bpos, bval, nParticles, nDims} } func pso(fn ff, y *state) *state { p := y.params v := make([]float64, y.nParticles) bpos := make([][]float64, y.nParticles) bval := make([]float64, y.nParticles) gbpos := make([]float64, y.nDims) gbval := math.Inf(1) for j := 0; j < y.nParticles; j++ { v[j] = fn(y.pos[j]) if v[j] < y.bval[j] { bpos[j] = y.pos[j] bval[j] = v[j] } else { bpos[j] = y.bpos[j] bval[j] = y.bval[j] } if bval[j] < gbval { gbval = bval[j] gbpos = bpos[j] } } rg := rand.Float64() pos := make([][]float64, y.nParticles) vel := make([][]float64, y.nParticles) for j := 0; j < y.nParticles; j++ { pos[j] = make([]float64, y.nDims) vel[j] = make([]float64, y.nDims) rp := rand.Float64() ok := true for z := 0; z < y.nDims; z++ { pos[j][z] = 0 vel[j][z] = 0 } for k := 0; k < y.nDims; k++ { vel[j][k] = p.omega*y.vel[j][k] + p.phip*rp*(bpos[j][k]-y.pos[j][k]) + p.phig*rg*(gbpos[k]-y.pos[j][k]) pos[j][k] = y.pos[j][k] + vel[j][k] ok = ok && y.min[k] < pos[j][k] && y.max[k] > pos[j][k] } if !ok { for k := 0; k < y.nDims; k++ { pos[j][k] = y.min[k] + (y.max[k]-y.min[k])*rand.Float64() } } } iter := 1 + y.iter return &state{iter, gbpos, gbval, y.min, y.max, y.params, pos, vel, bpos, bval, y.nParticles, y.nDims} } func iterate(fn ff, n int, y *state) *state { r := y for i := 0; i < n; i++ { r = pso(fn, r) } return r } func mccormick(x []float64) float64 { a, b := x[0], x[1] return math.Sin(a+b) + (a-b)*(a-b) + 1.0 + 2.5*b - 1.5*a } func michalewicz(x []float64) float64 { m := 10.0 sum := 0.0 for i := 1; i <= len(x); i++ { j := x[i-1] k := math.Sin(float64(i) * j * j / math.Pi) sum += math.Sin(j) * math.Pow(k, 2*m) } return -sum } func main() { rand.Seed(time.Now().UnixNano()) st := psoInit( []float64{-1.5, -3.0}, []float64{4.0, 4.0}, parameters{0.0, 0.6, 0.3}, 100, ) st = iterate(mccormick, 40, st) st.report("McCormick") fmt.Println("f(-.54719, -1.54719) :", mccormick([]float64{-.54719, -1.54719})) fmt.Println() st = psoInit( []float64{0.0, 0.0}, []float64{math.Pi, math.Pi}, parameters{0.3, 0.3, 0.3}, 1000, ) st = iterate(michalewicz, 30, st) st.report("Michalewicz (2D)") fmt.Println("f(2.20, 1.57)  :", michalewicz([]float64{2.2, 1.57}))
import java.util.Arrays; import java.util.Objects; import java.util.Random; import java.util.function.Function; public class App { static class Parameters { double omega; double phip; double phig; Parameters(double omega, double phip, double phig) { this.omega = omega; this.phip = phip; this.phig = phig; } } static class State { int iter; double[] gbpos; double gbval; double[] min; double[] max; Parameters parameters; double[][] pos; double[][] vel; double[][] bpos; double[] bval; int nParticles; int nDims; State(int iter, double[] gbpos, double gbval, double[] min, double[] max, Parameters parameters, double[][] pos, double[][] vel, double[][] bpos, double[] bval, int nParticles, int nDims) { this.iter = iter; this.gbpos = gbpos; this.gbval = gbval; this.min = min; this.max = max; this.parameters = parameters; this.pos = pos; this.vel = vel; this.bpos = bpos; this.bval = bval; this.nParticles = nParticles; this.nDims = nDims; } void report(String testfunc) { System.out.printf("Test Function  : %s\n", testfunc); System.out.printf("Iterations  : %d\n", iter); System.out.printf("Global Best Position : %s\n", Arrays.toString(gbpos)); System.out.printf("Global Best value  : %.15f\n", gbval); } } private static State psoInit(double[] min, double[] max, Parameters parameters, int nParticles) { int nDims = min.length; double[][] pos = new double[nParticles][]; for (int i = 0; i < nParticles; ++i) { pos[i] = min.clone(); } double[][] vel = new double[nParticles][nDims]; double[][] bpos = new double[nParticles][]; for (int i = 0; i < nParticles; ++i) { bpos[i] = min.clone(); } double[] bval = new double[nParticles]; for (int i = 0; i < bval.length; ++i) { bval[i] = Double.POSITIVE_INFINITY; } int iter = 0; double[] gbpos = new double[nDims]; for (int i = 0; i < gbpos.length; ++i) { gbpos[i] = Double.POSITIVE_INFINITY; } double gbval = Double.POSITIVE_INFINITY; return new State(iter, gbpos, gbval, min, max, parameters, pos, vel, bpos, bval, nParticles, nDims); } private static Random r = new Random(); private static State pso(Function<double[], Double> fn, State y) { Parameters p = y.parameters; double[] v = new double[y.nParticles]; double[][] bpos = new double[y.nParticles][]; for (int i = 0; i < y.nParticles; ++i) { bpos[i] = y.min.clone(); } double[] bval = new double[y.nParticles]; double[] gbpos = new double[y.nDims]; double gbval = Double.POSITIVE_INFINITY; for (int j = 0; j < y.nParticles; ++j) { v[j] = fn.apply(y.pos[j]); if (v[j] < y.bval[j]) { bpos[j] = y.pos[j]; bval[j] = v[j]; } else { bpos[j] = y.bpos[j]; bval[j] = y.bval[j]; } if (bval[j] < gbval) { gbval = bval[j]; gbpos = bpos[j]; } } double rg = r.nextDouble(); double[][] pos = new double[y.nParticles][y.nDims]; double[][] vel = new double[y.nParticles][y.nDims]; for (int j = 0; j < y.nParticles; ++j) { double rp = r.nextDouble(); boolean ok = true; Arrays.fill(vel[j], 0.0); Arrays.fill(pos[j], 0.0); for (int k = 0; k < y.nDims; ++k) { vel[j][k] = p.omega * y.vel[j][k] + p.phip * rp * (bpos[j][k] - y.pos[j][k]) + p.phig * rg * (gbpos[k] - y.pos[j][k]); pos[j][k] = y.pos[j][k] + vel[j][k]; ok = ok && y.min[k] < pos[j][k] && y.max[k] > pos[j][k]; } if (!ok) { for (int k = 0; k < y.nDims; ++k) { pos[j][k] = y.min[k] + (y.max[k] - y.min[k]) * r.nextDouble(); } } } int iter = 1 + y.iter; return new State( iter, gbpos, gbval, y.min, y.max, y.parameters, pos, vel, bpos, bval, y.nParticles, y.nDims ); } private static State iterate(Function<double[], Double> fn, int n, State y) { State r = y; if (n == Integer.MAX_VALUE) { State old = y; while (true) { r = pso(fn, r); if (Objects.equals(r, old)) break; old = r; } } else { for (int i = 0; i < n; ++i) { r = pso(fn, r); } } return r; } private static double mccormick(double[] x) { double a = x[0]; double b = x[1]; return Math.sin(a + b) + (a - b) * (a - b) + 1.0 + 2.5 * b - 1.5 * a; } private static double michalewicz(double[] x) { int m = 10; int d = x.length; double sum = 0.0; for (int i = 1; i < d; ++i) { double j = x[i - 1]; double k = Math.sin(i * j * j / Math.PI); sum += Math.sin(j) * Math.pow(k, 2.0 * m); } return -sum; } public static void main(String[] args) { State state = psoInit( new double[]{-1.5, -3.0}, new double[]{4.0, 4.0}, new Parameters(0.0, 0.6, 0.3), 100 ); state = iterate(App::mccormick, 40, state); state.report("McCormick"); System.out.printf("f(-.54719, -1.54719) : %.15f\n", mccormick(new double[]{-.54719, -1.54719})); System.out.println(); state = psoInit( new double[]{0.0, 0.0}, new double[]{Math.PI, Math.PI}, new Parameters(0.3, 3.0, 0.3), 1000 ); state = iterate(App::michalewicz, 30, state); state.report("Michalewicz (2D)"); System.out.printf("f(2.20, 1.57)  : %.15f\n", michalewicz(new double[]{2.20, 1.57})); } }
Rewrite the snippet below in Java so it works the same as the original Go code.
package main import "fmt" func f(s1, s2, sep string) string { return s1 + sep + sep + s2 } func main() { fmt.Println(f("Rosetta", "Code", ":")) }
public static void main(String[] args) { System.out.println(concat("Rosetta", "Code", ":")); } public static String concat(String a, String b, String c) { return a + c + c + b; } Rosetta::Code
Write the same code in Java as shown below in Go.
package main import ( "fmt" "math/big" ) func rank(l []uint) (r big.Int) { for _, n := range l { r.Lsh(&r, n+1) r.SetBit(&r, int(n), 1) } return } func unrank(n big.Int) (l []uint) { m := new(big.Int).Set(&n) for a := m.BitLen(); a > 0; { m.SetBit(m, a-1, 0) b := m.BitLen() l = append(l, uint(a-b-1)) a = b } return } func main() { var b big.Int for i := 0; i <= 10; i++ { b.SetInt64(int64(i)) u := unrank(b) r := rank(u) fmt.Println(i, u, &r) } b.SetString("12345678901234567890", 10) u := unrank(b) r := rank(u) fmt.Printf("\n%v\n%d\n%d\n", &b, u, &r) }
import java.math.BigInteger; import static java.util.Arrays.stream; import java.util.*; import static java.util.stream.Collectors.*; public class Test3 { static BigInteger rank(int[] x) { String s = stream(x).mapToObj(String::valueOf).collect(joining("F")); return new BigInteger(s, 16); } static List<BigInteger> unrank(BigInteger n) { BigInteger sixteen = BigInteger.valueOf(16); String s = ""; while (!n.equals(BigInteger.ZERO)) { s = "0123456789ABCDEF".charAt(n.mod(sixteen).intValue()) + s; n = n.divide(sixteen); } return stream(s.split("F")).map(x -> new BigInteger(x)).collect(toList()); } public static void main(String[] args) { int[] s = {1, 2, 3, 10, 100, 987654321}; System.out.println(Arrays.toString(s)); System.out.println(rank(s)); System.out.println(unrank(rank(s))); } }
Produce a functionally identical Java code for the snippet given in Go.
package main import ( "fmt" "io/ioutil" "os" ) func main() { fn := "myth" bx := ".backup" var err error if tf, err := os.Readlink(fn); err == nil { fn = tf } var fi os.FileInfo if fi, err = os.Stat(fn); err != nil { fmt.Println(err) return } if err = os.Rename(fn, fn+bx); err != nil { fmt.Println(err) return } err = ioutil.WriteFile(fn, []byte("you too!\n"), fi.Mode().Perm()) if err != nil { fmt.Println(err) } }
import java.io.File; import java.io.IOException; import java.io.PrintWriter; import java.nio.file.*; public class Backup { public static void saveWithBackup(String filename, String... data) throws IOException { Path file = Paths.get(filename).toRealPath(); File backFile = new File(filename + ".backup"); if(!backFile.exists()) { backFile.createNewFile(); } Path back = Paths.get(filename + ".backup").toRealPath(); Files.move(file, back, StandardCopyOption.REPLACE_EXISTING); try(PrintWriter out = new PrintWriter(file.toFile())){ for(int i = 0; i < data.length; i++) { out.print(data[i]); if(i < data.length - 1) { out.println(); } } } } public static void main(String[] args) { try { saveWithBackup("original.txt", "fourth", "fifth", "sixth"); } catch (IOException e) { System.err.println(e); } } }
Write a version of this Go function in Java with identical behavior.
package main import ( "fmt" "io/ioutil" "os" ) func main() { fn := "myth" bx := ".backup" var err error if tf, err := os.Readlink(fn); err == nil { fn = tf } var fi os.FileInfo if fi, err = os.Stat(fn); err != nil { fmt.Println(err) return } if err = os.Rename(fn, fn+bx); err != nil { fmt.Println(err) return } err = ioutil.WriteFile(fn, []byte("you too!\n"), fi.Mode().Perm()) if err != nil { fmt.Println(err) } }
import java.io.File; import java.io.IOException; import java.io.PrintWriter; import java.nio.file.*; public class Backup { public static void saveWithBackup(String filename, String... data) throws IOException { Path file = Paths.get(filename).toRealPath(); File backFile = new File(filename + ".backup"); if(!backFile.exists()) { backFile.createNewFile(); } Path back = Paths.get(filename + ".backup").toRealPath(); Files.move(file, back, StandardCopyOption.REPLACE_EXISTING); try(PrintWriter out = new PrintWriter(file.toFile())){ for(int i = 0; i < data.length; i++) { out.print(data[i]); if(i < data.length - 1) { out.println(); } } } } public static void main(String[] args) { try { saveWithBackup("original.txt", "fourth", "fifth", "sixth"); } catch (IOException e) { System.err.println(e); } } }
Convert this Go block to Java, preserving its control flow and logic.
package main import ( "fmt" "math/big" ) func repeatedAdd(bf *big.Float, times int) *big.Float { if times < 2 { return bf } var sum big.Float for i := 0; i < times; i++ { sum.Add(&sum, bf) } return &sum } func main() { s := "12345679" t := "123456790" e := 63 var bf, extra big.Float for n := -7; n <= 21; n++ { bf.SetString(fmt.Sprintf("%se%d", s, e)) extra.SetString(fmt.Sprintf("1e%d", e)) bf = *repeatedAdd(&bf, 81) bf.Add(&bf, &extra) fmt.Printf("%2d : %s\n", n, bf.String()) s = t + s e -= 9 } }
import java.math.BigDecimal; public class GeneralisedFloatingPointAddition { public static void main(String[] args) { BigDecimal oneExp72 = new BigDecimal("1E72"); for ( int i = 0 ; i <= 21+7 ; i++ ) { String s = "12345679"; for ( int j = 0 ; j < i ; j++ ) { s += "012345679"; } int exp = 63 - 9*i; s += "E" + exp; BigDecimal num = new BigDecimal(s).multiply(BigDecimal.valueOf(81)).add(new BigDecimal("1E" + exp)); System.out.printf("Test value (%s) equals computed value: %b. Computed = %s%n", oneExp72, num.compareTo(oneExp72) == 0 , num); } } }
Please provide an equivalent version of this Go code in Java.
package main import ( "fmt" "math/big" ) func repeatedAdd(bf *big.Float, times int) *big.Float { if times < 2 { return bf } var sum big.Float for i := 0; i < times; i++ { sum.Add(&sum, bf) } return &sum } func main() { s := "12345679" t := "123456790" e := 63 var bf, extra big.Float for n := -7; n <= 21; n++ { bf.SetString(fmt.Sprintf("%se%d", s, e)) extra.SetString(fmt.Sprintf("1e%d", e)) bf = *repeatedAdd(&bf, 81) bf.Add(&bf, &extra) fmt.Printf("%2d : %s\n", n, bf.String()) s = t + s e -= 9 } }
import java.math.BigDecimal; public class GeneralisedFloatingPointAddition { public static void main(String[] args) { BigDecimal oneExp72 = new BigDecimal("1E72"); for ( int i = 0 ; i <= 21+7 ; i++ ) { String s = "12345679"; for ( int j = 0 ; j < i ; j++ ) { s += "012345679"; } int exp = 63 - 9*i; s += "E" + exp; BigDecimal num = new BigDecimal(s).multiply(BigDecimal.valueOf(81)).add(new BigDecimal("1E" + exp)); System.out.printf("Test value (%s) equals computed value: %b. Computed = %s%n", oneExp72, num.compareTo(oneExp72) == 0 , num); } } }
Translate the given Go code snippet into Java without altering its behavior.
package main import ( "fmt" "strings" ) func reverseGender(s string) string { if strings.Contains(s, "She") { return strings.Replace(s, "She", "He", -1) } else if strings.Contains(s, "He") { return strings.Replace(s, "He", "She", -1) } return s } func main() { s := "She was a soul stripper. She took my heart!" t := reverseGender(s) fmt.Println(t) fmt.Println(reverseGender(t)) }
public class ReallyLameTranslationOfJ { public static void main(String[] args) { String s = "She was a soul stripper. She took my heart!"; System.out.println(cheapTrick(s)); System.out.println(cheapTrick(cheapTrick(s))); } static String cheapTrick(String s) { if (s.contains("She")) return s.replaceAll("She", "He"); else if(s.contains("He")) return s.replaceAll("He", "She"); return s; } }
Write the same code in Java as shown below in Go.
package main import ( "fmt" "strings" ) func reverseGender(s string) string { if strings.Contains(s, "She") { return strings.Replace(s, "She", "He", -1) } else if strings.Contains(s, "He") { return strings.Replace(s, "He", "She", -1) } return s } func main() { s := "She was a soul stripper. She took my heart!" t := reverseGender(s) fmt.Println(t) fmt.Println(reverseGender(t)) }
public class ReallyLameTranslationOfJ { public static void main(String[] args) { String s = "She was a soul stripper. She took my heart!"; System.out.println(cheapTrick(s)); System.out.println(cheapTrick(cheapTrick(s))); } static String cheapTrick(String s) { if (s.contains("She")) return s.replaceAll("She", "He"); else if(s.contains("He")) return s.replaceAll("He", "She"); return s; } }
Rewrite the snippet below in Java so it works the same as the original Go code.
package main import ( "bufio" "fmt" "log" "os" "os/exec" "strconv" "time" ) func main() { scanner := bufio.NewScanner(os.Stdin) number := 0 for number < 1 { fmt.Print("Enter number of seconds delay > 0 : ") scanner.Scan() input := scanner.Text() if err := scanner.Err(); err != nil { log.Fatal(err) } number, _ = strconv.Atoi(input) } filename := "" for filename == "" { fmt.Print("Enter name of .mp3 file to play (without extension) : ") scanner.Scan() filename = scanner.Text() if err := scanner.Err(); err != nil { log.Fatal(err) } } cls := "\033[2J\033[0;0H" fmt.Printf("%sAlarm will sound in %d seconds...", cls, number) time.Sleep(time.Duration(number) * time.Second) fmt.Printf(cls) cmd := exec.Command("play", filename+".mp3") if err := cmd.Run(); err != nil { log.Fatal(err) } }
import com.sun.javafx.application.PlatformImpl; import java.io.File; import java.util.Scanner; import java.util.concurrent.TimeUnit; import java.util.concurrent.atomic.AtomicBoolean; import javafx.scene.media.Media; import javafx.scene.media.MediaPlayer; public class AudioAlarm { public static void main(String[] args) throws InterruptedException { Scanner input = new Scanner(System.in); System.out.print("Enter a number of seconds: "); int seconds = Integer.parseInt(input.nextLine()); System.out.print("Enter a filename (must end with .mp3 or .wav): "); String audio = input.nextLine(); TimeUnit.SECONDS.sleep(seconds); Media media = new Media(new File(audio).toURI().toString()); AtomicBoolean stop = new AtomicBoolean(); Runnable onEnd = () -> stop.set(true); PlatformImpl.startup(() -> {}); MediaPlayer player = new MediaPlayer(media); player.setOnEndOfMedia(onEnd); player.setOnError(onEnd); player.setOnHalted(onEnd); player.play(); while (!stop.get()) { Thread.sleep(100); } System.exit(0); } }
Preserve the algorithm and functionality while converting the code from Go to Java.
package main import ( "fmt" "math" "strconv" "strings" ) func decToBin(d float64) string { whole := int64(math.Floor(d)) binary := strconv.FormatInt(whole, 2) + "." dd := d - float64(whole) for dd > 0.0 { r := dd * 2.0 if r >= 1.0 { binary += "1" dd = r - 1.0 } else { binary += "0" dd = r } } return binary } func binToDec(s string) float64 { ss := strings.Replace(s, ".", "", 1) num, _ := strconv.ParseInt(ss, 2, 64) ss = strings.Split(s, ".")[1] ss = strings.Replace(ss, "1", "0", -1) den, _ := strconv.ParseInt("1" + ss, 2, 64) return float64(num) / float64(den) } func main() { f := 23.34375 fmt.Printf("%v\t => %s\n", f, decToBin(f)) s := "1011.11101" fmt.Printf("%s\t => %v\n", s, binToDec(s)) }
import java.math.BigDecimal; import java.math.MathContext; import java.math.RoundingMode; public class DecimalToBinary { public static void main(String[] args) { for ( String s : new String[] {"23.34375", ".1", "3.1415926535897932"} ) { String binary = decimalToBinary(new BigDecimal(s)); System.out.printf("%s => %s%n", s, binary); System.out.printf("%s => %s%n", binary, binaryToDecimal(binary)); } } private static BigDecimal binaryToDecimal(String binary) { return binaryToDecimal(binary, 50); } private static BigDecimal binaryToDecimal(String binary, int digits) { int decimalPosition = binary.indexOf("."); String integer = decimalPosition >= 0 ? binary.substring(0, decimalPosition) : binary; String fractional = decimalPosition >= 0 ? binary.substring(decimalPosition+1) : ""; BigDecimal result = BigDecimal.ZERO; BigDecimal powTwo = BigDecimal.ONE; BigDecimal two = BigDecimal.valueOf(2); for ( char c : new StringBuilder(integer).reverse().toString().toCharArray() ) { result = result.add(powTwo.multiply(BigDecimal.valueOf(c - '0'))); powTwo = powTwo.multiply(two); } MathContext mc = new MathContext(digits); powTwo = BigDecimal.ONE; for ( char c : fractional.toCharArray() ) { powTwo = powTwo.divide(two); result = result.add(powTwo.multiply(BigDecimal.valueOf(c - '0')), mc); } return result; } private static String decimalToBinary(BigDecimal decimal) { return decimalToBinary(decimal, 50); } private static String decimalToBinary(BigDecimal decimal, int digits) { BigDecimal integer = decimal.setScale(0, RoundingMode.FLOOR); BigDecimal fractional = decimal.subtract(integer); StringBuilder sb = new StringBuilder(); BigDecimal two = BigDecimal.valueOf(2); BigDecimal zero = BigDecimal.ZERO; while ( integer.compareTo(zero) > 0 ) { BigDecimal[] result = integer.divideAndRemainder(two); sb.append(result[1]); integer = result[0]; } sb.reverse(); int count = 0; if ( fractional.compareTo(zero) != 0 ) { sb.append("."); } while ( fractional.compareTo(zero) != 0 ) { count++; fractional = fractional.multiply(two); sb.append(fractional.setScale(0, RoundingMode.FLOOR)); if ( fractional.compareTo(BigDecimal.ONE) >= 0 ) { fractional = fractional.subtract(BigDecimal.ONE); } if ( count >= digits ) { break; } } return sb.toString(); } }
Write the same code in Java as shown below in Go.
package main import ( "fmt" "math" "strconv" "strings" ) func decToBin(d float64) string { whole := int64(math.Floor(d)) binary := strconv.FormatInt(whole, 2) + "." dd := d - float64(whole) for dd > 0.0 { r := dd * 2.0 if r >= 1.0 { binary += "1" dd = r - 1.0 } else { binary += "0" dd = r } } return binary } func binToDec(s string) float64 { ss := strings.Replace(s, ".", "", 1) num, _ := strconv.ParseInt(ss, 2, 64) ss = strings.Split(s, ".")[1] ss = strings.Replace(ss, "1", "0", -1) den, _ := strconv.ParseInt("1" + ss, 2, 64) return float64(num) / float64(den) } func main() { f := 23.34375 fmt.Printf("%v\t => %s\n", f, decToBin(f)) s := "1011.11101" fmt.Printf("%s\t => %v\n", s, binToDec(s)) }
import java.math.BigDecimal; import java.math.MathContext; import java.math.RoundingMode; public class DecimalToBinary { public static void main(String[] args) { for ( String s : new String[] {"23.34375", ".1", "3.1415926535897932"} ) { String binary = decimalToBinary(new BigDecimal(s)); System.out.printf("%s => %s%n", s, binary); System.out.printf("%s => %s%n", binary, binaryToDecimal(binary)); } } private static BigDecimal binaryToDecimal(String binary) { return binaryToDecimal(binary, 50); } private static BigDecimal binaryToDecimal(String binary, int digits) { int decimalPosition = binary.indexOf("."); String integer = decimalPosition >= 0 ? binary.substring(0, decimalPosition) : binary; String fractional = decimalPosition >= 0 ? binary.substring(decimalPosition+1) : ""; BigDecimal result = BigDecimal.ZERO; BigDecimal powTwo = BigDecimal.ONE; BigDecimal two = BigDecimal.valueOf(2); for ( char c : new StringBuilder(integer).reverse().toString().toCharArray() ) { result = result.add(powTwo.multiply(BigDecimal.valueOf(c - '0'))); powTwo = powTwo.multiply(two); } MathContext mc = new MathContext(digits); powTwo = BigDecimal.ONE; for ( char c : fractional.toCharArray() ) { powTwo = powTwo.divide(two); result = result.add(powTwo.multiply(BigDecimal.valueOf(c - '0')), mc); } return result; } private static String decimalToBinary(BigDecimal decimal) { return decimalToBinary(decimal, 50); } private static String decimalToBinary(BigDecimal decimal, int digits) { BigDecimal integer = decimal.setScale(0, RoundingMode.FLOOR); BigDecimal fractional = decimal.subtract(integer); StringBuilder sb = new StringBuilder(); BigDecimal two = BigDecimal.valueOf(2); BigDecimal zero = BigDecimal.ZERO; while ( integer.compareTo(zero) > 0 ) { BigDecimal[] result = integer.divideAndRemainder(two); sb.append(result[1]); integer = result[0]; } sb.reverse(); int count = 0; if ( fractional.compareTo(zero) != 0 ) { sb.append("."); } while ( fractional.compareTo(zero) != 0 ) { count++; fractional = fractional.multiply(two); sb.append(fractional.setScale(0, RoundingMode.FLOOR)); if ( fractional.compareTo(BigDecimal.ONE) >= 0 ) { fractional = fractional.subtract(BigDecimal.ONE); } if ( count >= digits ) { break; } } return sb.toString(); } }
Generate a Java translation of this Go snippet without changing its computational steps.
package main import ( "bitbucket.org/binet/go-eval/pkg/eval" "fmt" "go/parser" "go/token" ) func main() { squareExpr := "x*x" fset := token.NewFileSet() squareAst, err := parser.ParseExpr(squareExpr) if err != nil { fmt.Println(err) return } w := eval.NewWorld() wVar := new(intV) err = w.DefineVar("x", eval.IntType, wVar) if err != nil { fmt.Println(err) return } squareCode, err := w.CompileExpr(fset, squareAst) if err != nil { fmt.Println(err) return } *wVar = 5 r0, err := squareCode.Run() if err != nil { fmt.Println(err) return } *wVar-- r1, err := squareCode.Run() if err != nil { fmt.Println(err) return } fmt.Println(r0.(eval.IntValue).Get(nil) - r1.(eval.IntValue).Get(nil)) } type intV int64 func (v *intV) String() string { return fmt.Sprint(*v) } func (v *intV) Get(*eval.Thread) int64 { return int64(*v) } func (v *intV) Set(_ *eval.Thread, x int64) { *v = intV(x) } func (v *intV) Assign(t *eval.Thread, o eval.Value) { *v = intV(o.(eval.IntValue).Get(t)) }
import java.io.File; import java.lang.reflect.Method; import java.net.URI; import java.util.Arrays; import javax.tools.JavaCompiler; import javax.tools.SimpleJavaFileObject; import javax.tools.ToolProvider; public class Eval { private static final String CLASS_NAME = "TempPleaseDeleteMe"; private static class StringCompiler extends SimpleJavaFileObject { final String m_sourceCode; private StringCompiler( final String sourceCode ) { super( URI.create( "string: m_sourceCode = sourceCode; } @Override public CharSequence getCharContent( final boolean ignoreEncodingErrors ) { return m_sourceCode; } private boolean compile() { final JavaCompiler javac = ToolProvider.getSystemJavaCompiler(); return javac.getTask( null, javac.getStandardFileManager( null, null, null ), null, null, null, Arrays.asList( this ) ).call(); } private double callEval( final double x ) throws Exception { final Class<?> clarse = Class.forName( CLASS_NAME ); final Method eval = clarse.getMethod( "eval", double.class ); return ( Double ) eval.invoke( null, x ); } } public static double evalWithX( final String code, final double x ) throws Exception { final StringCompiler sc = new StringCompiler( "class " + CLASS_NAME + "{public static double eval(double x){return (" + code + ");}}" ); if ( ! sc.compile() ) throw new RuntimeException( "Compiler error" ); return sc.callEval( x ); } public static void main( final String [] args ) throws Exception { final String expression = args [ 0 ]; final double x1 = Double.parseDouble( args [ 1 ] ); final double x2 = Double.parseDouble( args [ 2 ] ); System.out.println( evalWithX( expression, x1 ) - evalWithX( expression, x2 ) ); } }
Convert the following code from Go to Java, ensuring the logic remains intact.
package main import ( "bitbucket.org/binet/go-eval/pkg/eval" "fmt" "go/parser" "go/token" ) func main() { squareExpr := "x*x" fset := token.NewFileSet() squareAst, err := parser.ParseExpr(squareExpr) if err != nil { fmt.Println(err) return } w := eval.NewWorld() wVar := new(intV) err = w.DefineVar("x", eval.IntType, wVar) if err != nil { fmt.Println(err) return } squareCode, err := w.CompileExpr(fset, squareAst) if err != nil { fmt.Println(err) return } *wVar = 5 r0, err := squareCode.Run() if err != nil { fmt.Println(err) return } *wVar-- r1, err := squareCode.Run() if err != nil { fmt.Println(err) return } fmt.Println(r0.(eval.IntValue).Get(nil) - r1.(eval.IntValue).Get(nil)) } type intV int64 func (v *intV) String() string { return fmt.Sprint(*v) } func (v *intV) Get(*eval.Thread) int64 { return int64(*v) } func (v *intV) Set(_ *eval.Thread, x int64) { *v = intV(x) } func (v *intV) Assign(t *eval.Thread, o eval.Value) { *v = intV(o.(eval.IntValue).Get(t)) }
import java.io.File; import java.lang.reflect.Method; import java.net.URI; import java.util.Arrays; import javax.tools.JavaCompiler; import javax.tools.SimpleJavaFileObject; import javax.tools.ToolProvider; public class Eval { private static final String CLASS_NAME = "TempPleaseDeleteMe"; private static class StringCompiler extends SimpleJavaFileObject { final String m_sourceCode; private StringCompiler( final String sourceCode ) { super( URI.create( "string: m_sourceCode = sourceCode; } @Override public CharSequence getCharContent( final boolean ignoreEncodingErrors ) { return m_sourceCode; } private boolean compile() { final JavaCompiler javac = ToolProvider.getSystemJavaCompiler(); return javac.getTask( null, javac.getStandardFileManager( null, null, null ), null, null, null, Arrays.asList( this ) ).call(); } private double callEval( final double x ) throws Exception { final Class<?> clarse = Class.forName( CLASS_NAME ); final Method eval = clarse.getMethod( "eval", double.class ); return ( Double ) eval.invoke( null, x ); } } public static double evalWithX( final String code, final double x ) throws Exception { final StringCompiler sc = new StringCompiler( "class " + CLASS_NAME + "{public static double eval(double x){return (" + code + ");}}" ); if ( ! sc.compile() ) throw new RuntimeException( "Compiler error" ); return sc.callEval( x ); } public static void main( final String [] args ) throws Exception { final String expression = args [ 0 ]; final double x1 = Double.parseDouble( args [ 1 ] ); final double x2 = Double.parseDouble( args [ 2 ] ); System.out.println( evalWithX( expression, x1 ) - evalWithX( expression, x2 ) ); } }
Write a version of this Go function in Java with identical behavior.
package main import ( "fmt" "math/big" ) type mTerm struct { a, n, d int64 } var testCases = [][]mTerm{ {{1, 1, 2}, {1, 1, 3}}, {{2, 1, 3}, {1, 1, 7}}, {{4, 1, 5}, {-1, 1, 239}}, {{5, 1, 7}, {2, 3, 79}}, {{1, 1, 2}, {1, 1, 5}, {1, 1, 8}}, {{4, 1, 5}, {-1, 1, 70}, {1, 1, 99}}, {{5, 1, 7}, {4, 1, 53}, {2, 1, 4443}}, {{6, 1, 8}, {2, 1, 57}, {1, 1, 239}}, {{8, 1, 10}, {-1, 1, 239}, {-4, 1, 515}}, {{12, 1, 18}, {8, 1, 57}, {-5, 1, 239}}, {{16, 1, 21}, {3, 1, 239}, {4, 3, 1042}}, {{22, 1, 28}, {2, 1, 443}, {-5, 1, 1393}, {-10, 1, 11018}}, {{22, 1, 38}, {17, 7, 601}, {10, 7, 8149}}, {{44, 1, 57}, {7, 1, 239}, {-12, 1, 682}, {24, 1, 12943}}, {{88, 1, 172}, {51, 1, 239}, {32, 1, 682}, {44, 1, 5357}, {68, 1, 12943}}, {{88, 1, 172}, {51, 1, 239}, {32, 1, 682}, {44, 1, 5357}, {68, 1, 12944}}, } func main() { for _, m := range testCases { fmt.Printf("tan %v = %v\n", m, tans(m)) } } var one = big.NewRat(1, 1) func tans(m []mTerm) *big.Rat { if len(m) == 1 { return tanEval(m[0].a, big.NewRat(m[0].n, m[0].d)) } half := len(m) / 2 a := tans(m[:half]) b := tans(m[half:]) r := new(big.Rat) return r.Quo(new(big.Rat).Add(a, b), r.Sub(one, r.Mul(a, b))) } func tanEval(coef int64, f *big.Rat) *big.Rat { if coef == 1 { return f } if coef < 0 { r := tanEval(-coef, f) return r.Neg(r) } ca := coef / 2 cb := coef - ca a := tanEval(ca, f) b := tanEval(cb, f) r := new(big.Rat) return r.Quo(new(big.Rat).Add(a, b), r.Sub(one, r.Mul(a, b))) }
import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.io.IOException; import java.math.BigInteger; import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern; public class CheckMachinFormula { private static String FILE_NAME = "MachinFormula.txt"; public static void main(String[] args) { try { runPrivate(); } catch (Exception e) { e.printStackTrace(); } } private static void runPrivate() throws IOException { try (BufferedReader reader = new BufferedReader(new FileReader(new File(FILE_NAME)));) { String inLine = null; while ( (inLine = reader.readLine()) != null ) { String[] split = inLine.split("="); System.out.println(tanLeft(split[0].trim()) + " = " + split[1].trim().replaceAll("\\s+", " ") + " = " + tanRight(split[1].trim())); } } } private static String tanLeft(String formula) { if ( formula.compareTo("pi/4") == 0 ) { return "1"; } throw new RuntimeException("ERROR 104: Unknown left side: " + formula); } private static final Pattern ARCTAN_PATTERN = Pattern.compile("(-{0,1}\\d+)\\*arctan\\((\\d+)/(\\d+)\\)"); private static Fraction tanRight(String formula) { Matcher matcher = ARCTAN_PATTERN.matcher(formula); List<Term> terms = new ArrayList<>(); while ( matcher.find() ) { terms.add(new Term(Integer.parseInt(matcher.group(1)), new Fraction(matcher.group(2), matcher.group(3)))); } return evaluateArctan(terms); } private static Fraction evaluateArctan(List<Term> terms) { if ( terms.size() == 1 ) { Term term = terms.get(0); return evaluateArctan(term.coefficient, term.fraction); } int size = terms.size(); List<Term> left = terms.subList(0, (size+1) / 2); List<Term> right = terms.subList((size+1) / 2, size); return arctanFormula(evaluateArctan(left), evaluateArctan(right)); } private static Fraction evaluateArctan(int coefficient, Fraction fraction) { if ( coefficient == 1 ) { return fraction; } else if ( coefficient < 0 ) { return evaluateArctan(-coefficient, fraction).negate(); } if ( coefficient % 2 == 0 ) { Fraction f = evaluateArctan(coefficient/2, fraction); return arctanFormula(f, f); } Fraction a = evaluateArctan(coefficient/2, fraction); Fraction b = evaluateArctan(coefficient - (coefficient/2), fraction); return arctanFormula(a, b); } private static Fraction arctanFormula(Fraction f1, Fraction f2) { return f1.add(f2).divide(Fraction.ONE.subtract(f1.multiply(f2))); } private static class Fraction { public static final Fraction ONE = new Fraction("1", "1"); private BigInteger numerator; private BigInteger denominator; public Fraction(String num, String den) { numerator = new BigInteger(num); denominator = new BigInteger(den); } public Fraction(BigInteger num, BigInteger den) { numerator = num; denominator = den; } public Fraction negate() { return new Fraction(numerator.negate(), denominator); } public Fraction add(Fraction f) { BigInteger gcd = denominator.gcd(f.denominator); BigInteger first = numerator.multiply(f.denominator.divide(gcd)); BigInteger second = f.numerator.multiply(denominator.divide(gcd)); return new Fraction(first.add(second), denominator.multiply(f.denominator).divide(gcd)); } public Fraction subtract(Fraction f) { return add(f.negate()); } public Fraction multiply(Fraction f) { BigInteger num = numerator.multiply(f.numerator); BigInteger den = denominator.multiply(f.denominator); BigInteger gcd = num.gcd(den); return new Fraction(num.divide(gcd), den.divide(gcd)); } public Fraction divide(Fraction f) { return multiply(new Fraction(f.denominator, f.numerator)); } @Override public String toString() { if ( denominator.compareTo(BigInteger.ONE) == 0 ) { return numerator.toString(); } return numerator + " / " + denominator; } } private static class Term { private int coefficient; private Fraction fraction; public Term(int c, Fraction f) { coefficient = c; fraction = f; } } }
Produce a functionally identical Java code for the snippet given in Go.
package main import ( "fmt" "math/big" ) type mTerm struct { a, n, d int64 } var testCases = [][]mTerm{ {{1, 1, 2}, {1, 1, 3}}, {{2, 1, 3}, {1, 1, 7}}, {{4, 1, 5}, {-1, 1, 239}}, {{5, 1, 7}, {2, 3, 79}}, {{1, 1, 2}, {1, 1, 5}, {1, 1, 8}}, {{4, 1, 5}, {-1, 1, 70}, {1, 1, 99}}, {{5, 1, 7}, {4, 1, 53}, {2, 1, 4443}}, {{6, 1, 8}, {2, 1, 57}, {1, 1, 239}}, {{8, 1, 10}, {-1, 1, 239}, {-4, 1, 515}}, {{12, 1, 18}, {8, 1, 57}, {-5, 1, 239}}, {{16, 1, 21}, {3, 1, 239}, {4, 3, 1042}}, {{22, 1, 28}, {2, 1, 443}, {-5, 1, 1393}, {-10, 1, 11018}}, {{22, 1, 38}, {17, 7, 601}, {10, 7, 8149}}, {{44, 1, 57}, {7, 1, 239}, {-12, 1, 682}, {24, 1, 12943}}, {{88, 1, 172}, {51, 1, 239}, {32, 1, 682}, {44, 1, 5357}, {68, 1, 12943}}, {{88, 1, 172}, {51, 1, 239}, {32, 1, 682}, {44, 1, 5357}, {68, 1, 12944}}, } func main() { for _, m := range testCases { fmt.Printf("tan %v = %v\n", m, tans(m)) } } var one = big.NewRat(1, 1) func tans(m []mTerm) *big.Rat { if len(m) == 1 { return tanEval(m[0].a, big.NewRat(m[0].n, m[0].d)) } half := len(m) / 2 a := tans(m[:half]) b := tans(m[half:]) r := new(big.Rat) return r.Quo(new(big.Rat).Add(a, b), r.Sub(one, r.Mul(a, b))) } func tanEval(coef int64, f *big.Rat) *big.Rat { if coef == 1 { return f } if coef < 0 { r := tanEval(-coef, f) return r.Neg(r) } ca := coef / 2 cb := coef - ca a := tanEval(ca, f) b := tanEval(cb, f) r := new(big.Rat) return r.Quo(new(big.Rat).Add(a, b), r.Sub(one, r.Mul(a, b))) }
import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.io.IOException; import java.math.BigInteger; import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern; public class CheckMachinFormula { private static String FILE_NAME = "MachinFormula.txt"; public static void main(String[] args) { try { runPrivate(); } catch (Exception e) { e.printStackTrace(); } } private static void runPrivate() throws IOException { try (BufferedReader reader = new BufferedReader(new FileReader(new File(FILE_NAME)));) { String inLine = null; while ( (inLine = reader.readLine()) != null ) { String[] split = inLine.split("="); System.out.println(tanLeft(split[0].trim()) + " = " + split[1].trim().replaceAll("\\s+", " ") + " = " + tanRight(split[1].trim())); } } } private static String tanLeft(String formula) { if ( formula.compareTo("pi/4") == 0 ) { return "1"; } throw new RuntimeException("ERROR 104: Unknown left side: " + formula); } private static final Pattern ARCTAN_PATTERN = Pattern.compile("(-{0,1}\\d+)\\*arctan\\((\\d+)/(\\d+)\\)"); private static Fraction tanRight(String formula) { Matcher matcher = ARCTAN_PATTERN.matcher(formula); List<Term> terms = new ArrayList<>(); while ( matcher.find() ) { terms.add(new Term(Integer.parseInt(matcher.group(1)), new Fraction(matcher.group(2), matcher.group(3)))); } return evaluateArctan(terms); } private static Fraction evaluateArctan(List<Term> terms) { if ( terms.size() == 1 ) { Term term = terms.get(0); return evaluateArctan(term.coefficient, term.fraction); } int size = terms.size(); List<Term> left = terms.subList(0, (size+1) / 2); List<Term> right = terms.subList((size+1) / 2, size); return arctanFormula(evaluateArctan(left), evaluateArctan(right)); } private static Fraction evaluateArctan(int coefficient, Fraction fraction) { if ( coefficient == 1 ) { return fraction; } else if ( coefficient < 0 ) { return evaluateArctan(-coefficient, fraction).negate(); } if ( coefficient % 2 == 0 ) { Fraction f = evaluateArctan(coefficient/2, fraction); return arctanFormula(f, f); } Fraction a = evaluateArctan(coefficient/2, fraction); Fraction b = evaluateArctan(coefficient - (coefficient/2), fraction); return arctanFormula(a, b); } private static Fraction arctanFormula(Fraction f1, Fraction f2) { return f1.add(f2).divide(Fraction.ONE.subtract(f1.multiply(f2))); } private static class Fraction { public static final Fraction ONE = new Fraction("1", "1"); private BigInteger numerator; private BigInteger denominator; public Fraction(String num, String den) { numerator = new BigInteger(num); denominator = new BigInteger(den); } public Fraction(BigInteger num, BigInteger den) { numerator = num; denominator = den; } public Fraction negate() { return new Fraction(numerator.negate(), denominator); } public Fraction add(Fraction f) { BigInteger gcd = denominator.gcd(f.denominator); BigInteger first = numerator.multiply(f.denominator.divide(gcd)); BigInteger second = f.numerator.multiply(denominator.divide(gcd)); return new Fraction(first.add(second), denominator.multiply(f.denominator).divide(gcd)); } public Fraction subtract(Fraction f) { return add(f.negate()); } public Fraction multiply(Fraction f) { BigInteger num = numerator.multiply(f.numerator); BigInteger den = denominator.multiply(f.denominator); BigInteger gcd = num.gcd(den); return new Fraction(num.divide(gcd), den.divide(gcd)); } public Fraction divide(Fraction f) { return multiply(new Fraction(f.denominator, f.numerator)); } @Override public String toString() { if ( denominator.compareTo(BigInteger.ONE) == 0 ) { return numerator.toString(); } return numerator + " / " + denominator; } } private static class Term { private int coefficient; private Fraction fraction; public Term(int c, Fraction f) { coefficient = c; fraction = f; } } }
Preserve the algorithm and functionality while converting the code from Go to Java.
package main import ( "fmt" "math" "bytes" "encoding/binary" ) type testCase struct { hashCode string string } var testCases = []testCase{ {"d41d8cd98f00b204e9800998ecf8427e", ""}, {"0cc175b9c0f1b6a831c399e269772661", "a"}, {"900150983cd24fb0d6963f7d28e17f72", "abc"}, {"f96b697d7cb7938d525a2f31aaf161d0", "message digest"}, {"c3fcd3d76192e4007dfb496cca67e13b", "abcdefghijklmnopqrstuvwxyz"}, {"d174ab98d277d9f5a5611c2c9f419d9f", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"}, {"57edf4a22be3c955ac49da2e2107b67a", "12345678901234567890" + "123456789012345678901234567890123456789012345678901234567890"}, } func main() { for _, tc := range testCases { fmt.Printf("%s\n%x\n\n", tc.hashCode, md5(tc.string)) } } var shift = [...]uint{7, 12, 17, 22, 5, 9, 14, 20, 4, 11, 16, 23, 6, 10, 15, 21} var table [64]uint32 func init() { for i := range table { table[i] = uint32((1 << 32) * math.Abs(math.Sin(float64(i + 1)))) } } func md5(s string) (r [16]byte) { padded := bytes.NewBuffer([]byte(s)) padded.WriteByte(0x80) for padded.Len() % 64 != 56 { padded.WriteByte(0) } messageLenBits := uint64(len(s)) * 8 binary.Write(padded, binary.LittleEndian, messageLenBits) var a, b, c, d uint32 = 0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476 var buffer [16]uint32 for binary.Read(padded, binary.LittleEndian, buffer[:]) == nil { a1, b1, c1, d1 := a, b, c, d for j := 0; j < 64; j++ { var f uint32 bufferIndex := j round := j >> 4 switch round { case 0: f = (b1 & c1) | (^b1 & d1) case 1: f = (b1 & d1) | (c1 & ^d1) bufferIndex = (bufferIndex*5 + 1) & 0x0F case 2: f = b1 ^ c1 ^ d1 bufferIndex = (bufferIndex*3 + 5) & 0x0F case 3: f = c1 ^ (b1 | ^d1) bufferIndex = (bufferIndex * 7) & 0x0F } sa := shift[(round<<2)|(j&3)] a1 += f + buffer[bufferIndex] + table[j] a1, d1, c1, b1 = d1, c1, b1, a1<<sa|a1>>(32-sa)+b1 } a, b, c, d = a+a1, b+b1, c+c1, d+d1 } binary.Write(bytes.NewBuffer(r[:0]), binary.LittleEndian, []uint32{a, b, c, d}) return }
class MD5 { private static final int INIT_A = 0x67452301; private static final int INIT_B = (int)0xEFCDAB89L; private static final int INIT_C = (int)0x98BADCFEL; private static final int INIT_D = 0x10325476; private static final int[] SHIFT_AMTS = { 7, 12, 17, 22, 5, 9, 14, 20, 4, 11, 16, 23, 6, 10, 15, 21 }; private static final int[] TABLE_T = new int[64]; static { for (int i = 0; i < 64; i++) TABLE_T[i] = (int)(long)((1L << 32) * Math.abs(Math.sin(i + 1))); } public static byte[] computeMD5(byte[] message) { int messageLenBytes = message.length; int numBlocks = ((messageLenBytes + 8) >>> 6) + 1; int totalLen = numBlocks << 6; byte[] paddingBytes = new byte[totalLen - messageLenBytes]; paddingBytes[0] = (byte)0x80; long messageLenBits = (long)messageLenBytes << 3; for (int i = 0; i < 8; i++) { paddingBytes[paddingBytes.length - 8 + i] = (byte)messageLenBits; messageLenBits >>>= 8; } int a = INIT_A; int b = INIT_B; int c = INIT_C; int d = INIT_D; int[] buffer = new int[16]; for (int i = 0; i < numBlocks; i ++) { int index = i << 6; for (int j = 0; j < 64; j++, index++) buffer[j >>> 2] = ((int)((index < messageLenBytes) ? message[index] : paddingBytes[index - messageLenBytes]) << 24) | (buffer[j >>> 2] >>> 8); int originalA = a; int originalB = b; int originalC = c; int originalD = d; for (int j = 0; j < 64; j++) { int div16 = j >>> 4; int f = 0; int bufferIndex = j; switch (div16) { case 0: f = (b & c) | (~b & d); break; case 1: f = (b & d) | (c & ~d); bufferIndex = (bufferIndex * 5 + 1) & 0x0F; break; case 2: f = b ^ c ^ d; bufferIndex = (bufferIndex * 3 + 5) & 0x0F; break; case 3: f = c ^ (b | ~d); bufferIndex = (bufferIndex * 7) & 0x0F; break; } int temp = b + Integer.rotateLeft(a + f + buffer[bufferIndex] + TABLE_T[j], SHIFT_AMTS[(div16 << 2) | (j & 3)]); a = d; d = c; c = b; b = temp; } a += originalA; b += originalB; c += originalC; d += originalD; } byte[] md5 = new byte[16]; int count = 0; for (int i = 0; i < 4; i++) { int n = (i == 0) ? a : ((i == 1) ? b : ((i == 2) ? c : d)); for (int j = 0; j < 4; j++) { md5[count++] = (byte)n; n >>>= 8; } } return md5; } public static String toHexString(byte[] b) { StringBuilder sb = new StringBuilder(); for (int i = 0; i < b.length; i++) { sb.append(String.format("%02X", b[i] & 0xFF)); } return sb.toString(); } public static void main(String[] args) { String[] testStrings = { "", "a", "abc", "message digest", "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789", "12345678901234567890123456789012345678901234567890123456789012345678901234567890" }; for (String s : testStrings) System.out.println("0x" + toHexString(computeMD5(s.getBytes())) + " <== \"" + s + "\""); return; } }
Port the provided Go code into Java while preserving the original functionality.
package main import ( "fmt" "image" "image/color" "image/draw" "image/png" "math" "math/rand" "os" "time" ) type r2 struct { x, y float64 } type r2c struct { r2 c int } func kmpp(k int, data []r2c) { kMeans(data, kmppSeeds(k, data)) } func kmppSeeds(k int, data []r2c) []r2 { s := make([]r2, k) s[0] = data[rand.Intn(len(data))].r2 d2 := make([]float64, len(data)) for i := 1; i < k; i++ { var sum float64 for j, p := range data { _, dMin := nearest(p, s[:i]) d2[j] = dMin * dMin sum += d2[j] } target := rand.Float64() * sum j := 0 for sum = d2[0]; sum < target; sum += d2[j] { j++ } s[i] = data[j].r2 } return s } func nearest(p r2c, mean []r2) (int, float64) { iMin := 0 dMin := math.Hypot(p.x-mean[0].x, p.y-mean[0].y) for i := 1; i < len(mean); i++ { d := math.Hypot(p.x-mean[i].x, p.y-mean[i].y) if d < dMin { dMin = d iMin = i } } return iMin, dMin } func kMeans(data []r2c, mean []r2) { for i, p := range data { cMin, _ := nearest(p, mean) data[i].c = cMin } mLen := make([]int, len(mean)) for { for i := range mean { mean[i] = r2{} mLen[i] = 0 } for _, p := range data { mean[p.c].x += p.x mean[p.c].y += p.y mLen[p.c]++ } for i := range mean { inv := 1 / float64(mLen[i]) mean[i].x *= inv mean[i].y *= inv } var changes int for i, p := range data { if cMin, _ := nearest(p, mean); cMin != p.c { changes++ data[i].c = cMin } } if changes == 0 { return } } } type ecParam struct { k int nPoints int xBox, yBox int stdv int } func main() { ec := &ecParam{6, 30000, 300, 200, 30} origin, data := genECData(ec) vis(ec, data, "origin") fmt.Println("Data set origins:") fmt.Println(" x y") for _, o := range origin { fmt.Printf("%5.1f %5.1f\n", o.x, o.y) } kmpp(ec.k, data) fmt.Println( "\nCluster centroids, mean distance from centroid, number of points:") fmt.Println(" x y distance points") cent := make([]r2, ec.k) cLen := make([]int, ec.k) inv := make([]float64, ec.k) for _, p := range data { cent[p.c].x += p.x cent[p.c].y += p.y cLen[p.c]++ } for i, iLen := range cLen { inv[i] = 1 / float64(iLen) cent[i].x *= inv[i] cent[i].y *= inv[i] } dist := make([]float64, ec.k) for _, p := range data { dist[p.c] += math.Hypot(p.x-cent[p.c].x, p.y-cent[p.c].y) } for i, iLen := range cLen { fmt.Printf("%5.1f %5.1f %8.1f %6d\n", cent[i].x, cent[i].y, dist[i]*inv[i], iLen) } vis(ec, data, "clusters") } func genECData(ec *ecParam) (orig []r2, data []r2c) { rand.Seed(time.Now().UnixNano()) orig = make([]r2, ec.k) data = make([]r2c, ec.nPoints) for i, n := 0, 0; i < ec.k; i++ { x := rand.Float64() * float64(ec.xBox) y := rand.Float64() * float64(ec.yBox) orig[i] = r2{x, y} for j := ec.nPoints / ec.k; j > 0; j-- { data[n].x = rand.NormFloat64()*float64(ec.stdv) + x data[n].y = rand.NormFloat64()*float64(ec.stdv) + y data[n].c = i n++ } } return } func vis(ec *ecParam, data []r2c, fn string) { colors := make([]color.NRGBA, ec.k) for i := range colors { i3 := i * 3 third := i3 / ec.k frac := uint8((i3 % ec.k) * 255 / ec.k) switch third { case 0: colors[i] = color.NRGBA{frac, 255 - frac, 0, 255} case 1: colors[i] = color.NRGBA{0, frac, 255 - frac, 255} case 2: colors[i] = color.NRGBA{255 - frac, 0, frac, 255} } } bounds := image.Rect(-ec.stdv, -ec.stdv, ec.xBox+ec.stdv, ec.yBox+ec.stdv) im := image.NewNRGBA(bounds) draw.Draw(im, bounds, image.NewUniform(color.White), image.ZP, draw.Src) fMinX := float64(bounds.Min.X) fMaxX := float64(bounds.Max.X) fMinY := float64(bounds.Min.Y) fMaxY := float64(bounds.Max.Y) for _, p := range data { imx := math.Floor(p.x) imy := math.Floor(float64(ec.yBox) - p.y) if imx >= fMinX && imx < fMaxX && imy >= fMinY && imy < fMaxY { im.SetNRGBA(int(imx), int(imy), colors[p.c]) } } f, err := os.Create(fn + ".png") if err != nil { fmt.Println(err) return } err = png.Encode(f, im) if err != nil { fmt.Println(err) } err = f.Close() if err != nil { fmt.Println(err) } }
import java.util.Random; public class KMeansWithKpp{ public Point[] points; public Point[] centroids; Random rand; public int n; public int k; private KMeansWithKpp(){ } KMeansWithKpp(Point[] p, int clusters){ points = p; n = p.length; k = Math.max(1, clusters); centroids = new Point[k]; rand = new Random(); } private static double distance(Point a, Point b){ return (a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y); } private static int nearest(Point pt, Point[] others, int len){ double minD = Double.MAX_VALUE; int index = pt.group; len = Math.min(others.length, len); double dist; for (int i = 0; i < len; i++) { if (minD > (dist = distance(pt, others[i]))) { minD = dist; index = i; } } return index; } private static double nearestDistance(Point pt, Point[] others, int len){ double minD = Double.MAX_VALUE; len = Math.min(others.length, len); double dist; for (int i = 0; i < len; i++) { if (minD > (dist = distance(pt, others[i]))) { minD = dist; } } return minD; } private void kpp(){ centroids[0] = points[rand.nextInt(n)]; double[] dist = new double[n]; double sum = 0; for (int i = 1; i < k; i++) { for (int j = 0; j < n; j++) { dist[j] = nearestDistance(points[j], centroids, i); sum += dist[j]; } sum = (sum * rand.nextInt(Integer.MAX_VALUE)) / Integer.MAX_VALUE; for (int j = 0; j < n; j++) { if ((sum -= dist[j]) > 0) continue; centroids[i].x = points[j].x; centroids[i].y = points[j].y; } } for (int i = 0; i < n; i++) { points[i].group = nearest(points[i], centroids, k); } } public void kMeans(int maxTimes){ if (k == 1 || n <= 0) { return; } if(k >= n){ for(int i =0; i < n; i++){ points[i].group = i; } return; } maxTimes = Math.max(1, maxTimes); int changed; int bestPercent = n/1000; int minIndex; kpp(); do { for (Point c : centroids) { c.x = 0.0; c.y = 0.0; c.group = 0; } for (Point pt : points) { if(pt.group < 0 || pt.group > centroids.length){ pt.group = rand.nextInt(centroids.length); } centroids[pt.group].x += pt.x; centroids[pt.group].y = pt.y; centroids[pt.group].group++; } for (Point c : centroids) { c.x /= c.group; c.y /= c.group; } changed = 0; for (Point pt : points) { minIndex = nearest(pt, centroids, k); if (k != pt.group) { changed++; pt.group = minIndex; } } maxTimes--; } while (changed > bestPercent && maxTimes > 0); } } class Point{ public double x; public double y; public int group; Point(){ x = y = 0.0; group = 0; } public Point[] getRandomPlaneData(double minX, double maxX, double minY, double maxY, int size){ if (size <= 0) return null; double xdiff, ydiff; xdiff = maxX - minX; ydiff = maxY - minY; if (minX > maxX) { xdiff = minX - maxX; minX = maxX; } if (maxY < minY) { ydiff = minY - maxY; minY = maxY; } Point[] data = new Point[size]; Random rand = new Random(); for (int i = 0; i < size; i++) { data[i].x = minX + (xdiff * rand.nextInt(Integer.MAX_VALUE)) / Integer.MAX_VALUE; data[i].y = minY + (ydiff * rand.nextInt(Integer.MAX_VALUE)) / Integer.MAX_VALUE; } return data; } public Point[] getRandomPolarData(double radius, int size){ if (size <= 0) { return null; } Point[] data = new Point[size]; double radi, arg; Random rand = new Random(); for (int i = 0; i < size; i++) { radi = (radius * rand.nextInt(Integer.MAX_VALUE)) / Integer.MAX_VALUE; arg = (2 * Math.PI * rand.nextInt(Integer.MAX_VALUE)) / Integer.MAX_VALUE; data[i].x = radi * Math.cos(arg); data[i].y = radi * Math.sin(arg); } return data; } }
Please provide an equivalent version of this Go code in Java.
package main import ( "bytes" "fmt" "math/rand" "time" ) type maze struct { c2 [][]byte h2 [][]byte v2 [][]byte } func newMaze(rows, cols int) *maze { c := make([]byte, rows*cols) h := bytes.Repeat([]byte{'-'}, rows*cols) v := bytes.Repeat([]byte{'|'}, rows*cols) c2 := make([][]byte, rows) h2 := make([][]byte, rows) v2 := make([][]byte, rows) for i := range h2 { c2[i] = c[i*cols : (i+1)*cols] h2[i] = h[i*cols : (i+1)*cols] v2[i] = v[i*cols : (i+1)*cols] } return &maze{c2, h2, v2} } func (m *maze) String() string { hWall := []byte("+---") hOpen := []byte("+ ") vWall := []byte("| ") vOpen := []byte(" ") rightCorner := []byte("+\n") rightWall := []byte("|\n") var b []byte for r, hw := range m.h2 { for _, h := range hw { if h == '-' || r == 0 { b = append(b, hWall...) } else { b = append(b, hOpen...) if h != '-' && h != 0 { b[len(b)-2] = h } } } b = append(b, rightCorner...) for c, vw := range m.v2[r] { if vw == '|' || c == 0 { b = append(b, vWall...) } else { b = append(b, vOpen...) if vw != '|' && vw != 0 { b[len(b)-4] = vw } } if m.c2[r][c] != 0 { b[len(b)-2] = m.c2[r][c] } } b = append(b, rightWall...) } for _ = range m.h2[0] { b = append(b, hWall...) } b = append(b, rightCorner...) return string(b) } func (m *maze) gen() { m.g2(rand.Intn(len(m.c2)), rand.Intn(len(m.c2[0]))) } const ( up = iota dn rt lf ) func (m *maze) g2(r, c int) { m.c2[r][c] = ' ' for _, dir := range rand.Perm(4) { switch dir { case up: if r > 0 && m.c2[r-1][c] == 0 { m.h2[r][c] = 0 m.g2(r-1, c) } case lf: if c > 0 && m.c2[r][c-1] == 0 { m.v2[r][c] = 0 m.g2(r, c-1) } case dn: if r < len(m.c2)-1 && m.c2[r+1][c] == 0 { m.h2[r+1][c] = 0 m.g2(r+1, c) } case rt: if c < len(m.c2[0])-1 && m.c2[r][c+1] == 0 { m.v2[r][c+1] = 0 m.g2(r, c+1) } } } } func main() { rand.Seed(time.Now().UnixNano()) const height = 4 const width = 7 m := newMaze(height, width) m.gen() m.solve( rand.Intn(height), rand.Intn(width), rand.Intn(height), rand.Intn(width)) fmt.Print(m) } func (m *maze) solve(ra, ca, rz, cz int) { var rSolve func(ra, ca, dir int) bool rSolve = func(r, c, dir int) bool { if r == rz && c == cz { m.c2[r][c] = 'F' return true } if dir != dn && m.h2[r][c] == 0 { if rSolve(r-1, c, up) { m.c2[r][c] = '^' m.h2[r][c] = '^' return true } } if dir != up && r+1 < len(m.h2) && m.h2[r+1][c] == 0 { if rSolve(r+1, c, dn) { m.c2[r][c] = 'v' m.h2[r+1][c] = 'v' return true } } if dir != lf && c+1 < len(m.v2[0]) && m.v2[r][c+1] == 0 { if rSolve(r, c+1, rt) { m.c2[r][c] = '>' m.v2[r][c+1] = '>' return true } } if dir != rt && m.v2[r][c] == 0 { if rSolve(r, c-1, lf) { m.c2[r][c] = '<' m.v2[r][c] = '<' return true } } return false } rSolve(ra, ca, -1) m.c2[ra][ca] = 'S' }
import java.io.*; import java.util.*; public class MazeSolver { private static String[] readLines (InputStream f) throws IOException { BufferedReader r = new BufferedReader (new InputStreamReader (f, "US-ASCII")); ArrayList<String> lines = new ArrayList<String>(); String line; while ((line = r.readLine()) != null) lines.add (line); return lines.toArray(new String[0]); } private static char[][] decimateHorizontally (String[] lines) { final int width = (lines[0].length() + 1) / 2; char[][] c = new char[lines.length][width]; for (int i = 0 ; i < lines.length ; i++) for (int j = 0 ; j < width ; j++) c[i][j] = lines[i].charAt (j * 2); return c; } private static boolean solveMazeRecursively (char[][] maze, int x, int y, int d) { boolean ok = false; for (int i = 0 ; i < 4 && !ok ; i++) if (i != d) switch (i) { case 0: if (maze[y-1][x] == ' ') ok = solveMazeRecursively (maze, x, y - 2, 2); break; case 1: if (maze[y][x+1] == ' ') ok = solveMazeRecursively (maze, x + 2, y, 3); break; case 2: if (maze[y+1][x] == ' ') ok = solveMazeRecursively (maze, x, y + 2, 0); break; case 3: if (maze[y][x-1] == ' ') ok = solveMazeRecursively (maze, x - 2, y, 1); break; } if (x == 1 && y == 1) ok = true; if (ok) { maze[y][x] = '*'; switch (d) { case 0: maze[y-1][x] = '*'; break; case 1: maze[y][x+1] = '*'; break; case 2: maze[y+1][x] = '*'; break; case 3: maze[y][x-1] = '*'; break; } } return ok; } private static void solveMaze (char[][] maze) { solveMazeRecursively (maze, maze[0].length - 2, maze.length - 2, -1); } private static String[] expandHorizontally (char[][] maze) { char[] tmp = new char[3]; String[] lines = new String[maze.length]; for (int i = 0 ; i < maze.length ; i++) { StringBuilder sb = new StringBuilder(maze[i].length * 2); for (int j = 0 ; j < maze[i].length ; j++) if (j % 2 == 0) sb.append (maze[i][j]); else { tmp[0] = tmp[1] = tmp[2] = maze[i][j]; if (tmp[1] == '*') tmp[0] = tmp[2] = ' '; sb.append (tmp); } lines[i] = sb.toString(); } return lines; } public static void main (String[] args) throws IOException { InputStream f = (args.length > 0 ? new FileInputStream (args[0]) : System.in); String[] lines = readLines (f); char[][] maze = decimateHorizontally (lines); solveMaze (maze); String[] solvedLines = expandHorizontally (maze); for (int i = 0 ; i < solvedLines.length ; i++) System.out.println (solvedLines[i]); } }
Rewrite this program in Java while keeping its functionality equivalent to the Go version.
package main import ( "fmt" "log" "math/rand" "time" ) func generate(from, to int64) { if to < from || from < 0 { log.Fatal("Invalid range.") } span := to - from + 1 generated := make([]bool, span) count := span for count > 0 { n := from + rand.Int63n(span) if !generated[n-from] { generated[n-from] = true fmt.Printf("%2d ", n) count-- } } fmt.Println() } func main() { rand.Seed(time.Now().UnixNano()) for i := 1; i <= 5; i++ { generate(1, 20) } }
import java.util.*; public class RandomShuffle { public static void main(String[] args) { Random rand = new Random(); List<Integer> list = new ArrayList<>(); for (int j = 1; j <= 20; ++j) list.add(j); Collections.shuffle(list, rand); System.out.println(list); } }
Port the provided Go code into Java while preserving the original functionality.
package main import "fmt" type solution struct{ peg, over, land int } type move struct{ from, to int } var emptyStart = 1 var board [16]bool var jumpMoves = [16][]move{ {}, {{2, 4}, {3, 6}}, {{4, 7}, {5, 9}}, {{5, 8}, {6, 10}}, {{2, 1}, {5, 6}, {7, 11}, {8, 13}}, {{8, 12}, {9, 14}}, {{3, 1}, {5, 4}, {9, 13}, {10, 15}}, {{4, 2}, {8, 9}}, {{5, 3}, {9, 10}}, {{5, 2}, {8, 7}}, {{9, 8}}, {{12, 13}}, {{8, 5}, {13, 14}}, {{8, 4}, {9, 6}, {12, 11}, {14, 15}}, {{9, 5}, {13, 12}}, {{10, 6}, {14, 13}}, } var solutions []solution func initBoard() { for i := 1; i < 16; i++ { board[i] = true } board[emptyStart] = false } func (sol solution) split() (int, int, int) { return sol.peg, sol.over, sol.land } func (mv move) split() (int, int) { return mv.from, mv.to } func drawBoard() { var pegs [16]byte for i := 1; i < 16; i++ { if board[i] { pegs[i] = fmt.Sprintf("%X", i)[0] } else { pegs[i] = '-' } } fmt.Printf(" %c\n", pegs[1]) fmt.Printf(" %c %c\n", pegs[2], pegs[3]) fmt.Printf(" %c %c %c\n", pegs[4], pegs[5], pegs[6]) fmt.Printf(" %c %c %c %c\n", pegs[7], pegs[8], pegs[9], pegs[10]) fmt.Printf(" %c %c %c %c %c\n", pegs[11], pegs[12], pegs[13], pegs[14], pegs[15]) } func solved() bool { count := 0 for _, b := range board { if b { count++ } } return count == 1 } func solve() { if solved() { return } for peg := 1; peg < 16; peg++ { if board[peg] { for _, mv := range jumpMoves[peg] { over, land := mv.split() if board[over] && !board[land] { saveBoard := board board[peg] = false board[over] = false board[land] = true solutions = append(solutions, solution{peg, over, land}) solve() if solved() { return } board = saveBoard solutions = solutions[:len(solutions)-1] } } } } } func main() { initBoard() solve() initBoard() drawBoard() fmt.Printf("Starting with peg %X removed\n\n", emptyStart) for _, solution := range solutions { peg, over, land := solution.split() board[peg] = false board[over] = false board[land] = true drawBoard() fmt.Printf("Peg %X jumped over %X to land on %X\n\n", peg, over, land) } }
import java.util.ArrayList; import java.util.Arrays; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Stack; public class IQPuzzle { public static void main(String[] args) { System.out.printf(" "); for ( int start = 1 ; start < Puzzle.MAX_PEGS ; start++ ) { System.out.printf("  %,6d", start); } System.out.printf("%n"); for ( int start = 1 ; start < Puzzle.MAX_PEGS ; start++ ) { System.out.printf("%2d", start); Map<Integer,Integer> solutions = solve(start); for ( int end = 1 ; end < Puzzle.MAX_PEGS ; end++ ) { System.out.printf("  %,6d", solutions.containsKey(end) ? solutions.get(end) : 0); } System.out.printf("%n"); } int moveNum = 0; System.out.printf("%nOne Solution:%n"); for ( Move m : oneSolution ) { moveNum++; System.out.printf("Move %d = %s%n", moveNum, m); } } private static List<Move> oneSolution = null; private static Map<Integer, Integer> solve(int emptyPeg) { Puzzle puzzle = new Puzzle(emptyPeg); Map<Integer,Integer> solutions = new HashMap<>(); Stack<Puzzle> stack = new Stack<Puzzle>(); stack.push(puzzle); while ( ! stack.isEmpty() ) { Puzzle p = stack.pop(); if ( p.solved() ) { solutions.merge(p.getLastPeg(), 1, (v1,v2) -> v1 + v2); if ( oneSolution == null ) { oneSolution = p.moves; } continue; } for ( Move move : p.getValidMoves() ) { Puzzle pMove = p.move(move); stack.add(pMove); } } return solutions; } private static class Puzzle { public static int MAX_PEGS = 16; private boolean[] pegs = new boolean[MAX_PEGS]; private List<Move> moves; public Puzzle(int emptyPeg) { for ( int i = 1 ; i < MAX_PEGS ; i++ ) { pegs[i] = true; } pegs[emptyPeg] = false; moves = new ArrayList<>(); } public Puzzle() { for ( int i = 1 ; i < MAX_PEGS ; i++ ) { pegs[i] = true; } moves = new ArrayList<>(); } private static Map<Integer,List<Move>> validMoves = new HashMap<>(); static { validMoves.put(1, Arrays.asList(new Move(1, 2, 4), new Move(1, 3, 6))); validMoves.put(2, Arrays.asList(new Move(2, 4, 7), new Move(2, 5, 9))); validMoves.put(3, Arrays.asList(new Move(3, 5, 8), new Move(3, 6, 10))); validMoves.put(4, Arrays.asList(new Move(4, 2, 1), new Move(4, 5, 6), new Move(4, 8, 13), new Move(4, 7, 11))); validMoves.put(5, Arrays.asList(new Move(5, 8, 12), new Move(5, 9, 14))); validMoves.put(6, Arrays.asList(new Move(6, 3, 1), new Move(6, 5, 4), new Move(6, 9, 13), new Move(6, 10, 15))); validMoves.put(7, Arrays.asList(new Move(7, 4, 2), new Move(7, 8, 9))); validMoves.put(8, Arrays.asList(new Move(8, 5, 3), new Move(8, 9, 10))); validMoves.put(9, Arrays.asList(new Move(9, 5, 2), new Move(9, 8, 7))); validMoves.put(10, Arrays.asList(new Move(10, 6, 3), new Move(10, 9, 8))); validMoves.put(11, Arrays.asList(new Move(11, 7, 4), new Move(11, 12, 13))); validMoves.put(12, Arrays.asList(new Move(12, 8, 5), new Move(12, 13, 14))); validMoves.put(13, Arrays.asList(new Move(13, 12, 11), new Move(13, 8, 4), new Move(13, 9, 6), new Move(13, 14, 15))); validMoves.put(14, Arrays.asList(new Move(14, 13, 12), new Move(14, 9, 5))); validMoves.put(15, Arrays.asList(new Move(15, 14, 13), new Move(15, 10, 6))); } public List<Move> getValidMoves() { List<Move> moves = new ArrayList<Move>(); for ( int i = 1 ; i < MAX_PEGS ; i++ ) { if ( pegs[i] ) { for ( Move testMove : validMoves.get(i) ) { if ( pegs[testMove.jump] && ! pegs[testMove.end] ) { moves.add(testMove); } } } } return moves; } public boolean solved() { boolean foundFirstPeg = false; for ( int i = 1 ; i < MAX_PEGS ; i++ ) { if ( pegs[i] ) { if ( foundFirstPeg ) { return false; } foundFirstPeg = true; } } return true; } public Puzzle move(Move move) { Puzzle p = new Puzzle(); if ( ! pegs[move.start] || ! pegs[move.jump] || pegs[move.end] ) { throw new RuntimeException("Invalid move."); } for ( int i = 1 ; i < MAX_PEGS ; i++ ) { p.pegs[i] = pegs[i]; } p.pegs[move.start] = false; p.pegs[move.jump] = false; p.pegs[move.end] = true; for ( Move m : moves ) { p.moves.add(new Move(m.start, m.jump, m.end)); } p.moves.add(new Move(move.start, move.jump, move.end)); return p; } public int getLastPeg() { for ( int i = 1 ; i < MAX_PEGS ; i++ ) { if ( pegs[i] ) { return i; } } throw new RuntimeException("ERROR: Illegal position."); } @Override public String toString() { StringBuilder sb = new StringBuilder(); sb.append("["); for ( int i = 1 ; i < MAX_PEGS ; i++ ) { sb.append(pegs[i] ? 1 : 0); sb.append(","); } sb.setLength(sb.length()-1); sb.append("]"); return sb.toString(); } } private static class Move { int start; int jump; int end; public Move(int s, int j, int e) { start = s; jump = j; end = e; } @Override public String toString() { StringBuilder sb = new StringBuilder(); sb.append("{"); sb.append("s=" + start); sb.append(", j=" + jump); sb.append(", e=" + end); sb.append("}"); return sb.toString(); } } }
Transform the following Go implementation into Java, maintaining the same output and logic.
package main import ( "image" "image/color" "image/png" "log" "math/rand" "os" "time" ) func main() { rand.Seed(time.Now().UnixNano()) img := image.NewNRGBA(image.Rect(0, 0, 1000, 1000)) for x := 0; x < 1000; x++ { for y := 0; y < 1000; y++ { col := color.RGBA{uint8(rand.Intn(256)), uint8(rand.Intn(256)), uint8(rand.Intn(256)), 255} img.Set(x, y, col) } } fileName := "pseudorandom_number_generator.png" imgFile, err := os.Create(fileName) if err != nil { log.Fatal(err) } defer imgFile.Close() if err := png.Encode(imgFile, img); err != nil { imgFile.Close() log.Fatal(err) } }
import javax.imageio.ImageIO; import java.awt.*; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import java.math.BigInteger; import java.security.SecureRandom; import java.util.Random; import java.util.Scanner; public class csprngBBS { public static Scanner input = new Scanner(System.in); private static final String fileformat = "png"; private static String bitsStri = ""; private static String parityEven = ""; private static String leastSig = ""; private static String randomJavaUtil = ""; private static int width = 0; private static int BIT_LENGTH = 0; private static final Random rand = new SecureRandom(); private static BigInteger p = null; private static BigInteger q = null; private static BigInteger m = null; private static BigInteger seed = null; private static BigInteger seedFinal = null; private static final Random randMathUtil = new SecureRandom(); public static void main(String[] args) throws IOException { System.out.print("Width: "); width = input.nextInt(); System.out.print("Bit-Length: "); BIT_LENGTH = input.nextInt(); System.out.print("Generator format: "); String useGenerator = input.next(); p = BigInteger.probablePrime(BIT_LENGTH, rand); q = BigInteger.probablePrime(BIT_LENGTH, rand); m = p.multiply(q); seed = BigInteger.probablePrime(BIT_LENGTH,rand); seedFinal = seed.add(BigInteger.ZERO); if(useGenerator.contains("parity") && useGenerator.contains("significant")) { findLeastSignificant(); findBitParityEven(); createImage(parityEven, "parityEven"); createImage(leastSig, "significant"); } if(useGenerator.contains("parity") && !useGenerator.contains("significant")){ findBitParityEven(); } if(useGenerator.contains("significant") && !useGenerator.contains("parity")){ findLeastSignificant(); createImage(leastSig, "significant"); } if(useGenerator.contains("util")){ findRandomJava(randMathUtil); createImage(randomJavaUtil, "randomUtilJava"); } } public static void findRandomJava(Random random){ for(int x = 1; x <= Math.pow(width, 2); x++){ randomJavaUtil += random.nextInt(2); } } public static void findBitParityEven(){ for(int x = 1; x <= Math.pow(width, 2); x++) { seed = seed.pow(2).mod(m); bitsStri = convertBinary(seed); char[] bits = bitsStri.toCharArray(); int counter = 0; for (char bit : bits) { if (bit == '1') { counter++; } } if (counter % 2 != 0) { parityEven += "1"; } else { parityEven += "0"; } } } public static void findLeastSignificant(){ seed = seedFinal; for(int x = 1; x <= Math.pow(width, 2); x++){ seed = seed.pow(2).mod(m); leastSig += bitsStri.substring(bitsStri.length() - 1); } } public static String convertBinary(BigInteger value){ StringBuilder total = new StringBuilder(); BigInteger two = BigInteger.TWO; while(value.compareTo(BigInteger.ZERO) > 0){ total.append(value.mod(two)); value = value.divide(two); } return total.reverse().toString(); } public static void createImage(String useThis, String fileName) throws IOException { int length = csprngBBS.width; BufferedImage bufferedImage = new BufferedImage(length, length, 1); Graphics2D g2d = bufferedImage.createGraphics(); for (int y = 1; y <= length; y++) { for (int x = 1; x <= length; x++) { if (useThis.startsWith("1")) { useThis = useThis.substring(1); g2d.setColor(Color.BLACK); g2d.fillRect(x, y, 1, 1); } else if (useThis.startsWith("0")) { useThis = useThis.substring(1); g2d.setColor(Color.WHITE); g2d.fillRect(x, y, 1, 1); } } System.out.print(y + "\t"); } g2d.dispose(); File file = new File("REPLACEFILEPATHHERE" + fileName + "." + fileformat); ImageIO.write(bufferedImage, fileformat, file); } }
Port the following code from Go to Java with equivalent syntax and logic.
package main import ( "fmt" "sort" ) func fourFaceCombs() (res [][4]int) { found := make([]bool, 256) for i := 1; i <= 4; i++ { for j := 1; j <= 4; j++ { for k := 1; k <= 4; k++ { for l := 1; l <= 4; l++ { c := [4]int{i, j, k, l} sort.Ints(c[:]) key := 64*(c[0]-1) + 16*(c[1]-1) + 4*(c[2]-1) + (c[3] - 1) if !found[key] { found[key] = true res = append(res, c) } } } } } return } func cmp(x, y [4]int) int { xw := 0 yw := 0 for i := 0; i < 4; i++ { for j := 0; j < 4; j++ { if x[i] > y[j] { xw++ } else if y[j] > x[i] { yw++ } } } if xw < yw { return -1 } else if xw > yw { return 1 } return 0 } func findIntransitive3(cs [][4]int) (res [][3][4]int) { var c = len(cs) for i := 0; i < c; i++ { for j := 0; j < c; j++ { for k := 0; k < c; k++ { first := cmp(cs[i], cs[j]) if first == -1 { second := cmp(cs[j], cs[k]) if second == -1 { third := cmp(cs[i], cs[k]) if third == 1 { res = append(res, [3][4]int{cs[i], cs[j], cs[k]}) } } } } } } return } func findIntransitive4(cs [][4]int) (res [][4][4]int) { c := len(cs) for i := 0; i < c; i++ { for j := 0; j < c; j++ { for k := 0; k < c; k++ { for l := 0; l < c; l++ { first := cmp(cs[i], cs[j]) if first == -1 { second := cmp(cs[j], cs[k]) if second == -1 { third := cmp(cs[k], cs[l]) if third == -1 { fourth := cmp(cs[i], cs[l]) if fourth == 1 { res = append(res, [4][4]int{cs[i], cs[j], cs[k], cs[l]}) } } } } } } } } return } func main() { combs := fourFaceCombs() fmt.Println("Number of eligible 4-faced dice", len(combs)) it3 := findIntransitive3(combs) fmt.Printf("\n%d ordered lists of 3 non-transitive dice found, namely:\n", len(it3)) for _, a := range it3 { fmt.Println(a) } it4 := findIntransitive4(combs) fmt.Printf("\n%d ordered lists of 4 non-transitive dice found, namely:\n", len(it4)) for _, a := range it4 { fmt.Println(a) } }
import java.util.ArrayList; import java.util.HashSet; import java.util.List; import java.util.Set; import java.util.stream.Collectors; import java.util.stream.IntStream; public class Main { private static List<List<Integer>> fourFaceCombos() { List<List<Integer>> res = new ArrayList<>(); Set<Integer> found = new HashSet<>(); for (int i = 1; i <= 4; i++) { for (int j = 1; j <= 4; j++) { for (int k = 1; k <= 4; k++) { for (int l = 1; l <= 4; l++) { List<Integer> c = IntStream.of(i, j, k, l).sorted().boxed().collect(Collectors.toList()); int key = 64 * (c.get(0) - 1) + 16 * (c.get(1) - 1) + 4 * (c.get(2) - 1) + (c.get(3) - 1); if (found.add(key)) { res.add(c); } } } } } return res; } private static int cmp(List<Integer> x, List<Integer> y) { int xw = 0; int yw = 0; for (int i = 0; i < 4; i++) { for (int j = 0; j < 4; j++) { if (x.get(i) > y.get(j)) { xw++; } else if (x.get(i) < y.get(j)) { yw++; } } } return Integer.compare(xw, yw); } private static List<List<List<Integer>>> findIntransitive3(List<List<Integer>> cs) { int c = cs.size(); List<List<List<Integer>>> res = new ArrayList<>(); for (int i = 0; i < c; i++) { for (int j = 0; j < c; j++) { if (cmp(cs.get(i), cs.get(j)) == -1) { for (List<Integer> kl : cs) { if (cmp(cs.get(j), kl) == -1 && cmp(kl, cs.get(i)) == -1) { res.add(List.of(cs.get(i), cs.get(j), kl)); } } } } } return res; } private static List<List<List<Integer>>> findIntransitive4(List<List<Integer>> cs) { int c = cs.size(); List<List<List<Integer>>> res = new ArrayList<>(); for (int i = 0; i < c; i++) { for (int j = 0; j < c; j++) { if (cmp(cs.get(i), cs.get(j)) == -1) { for (int k = 0; k < cs.size(); k++) { if (cmp(cs.get(j), cs.get(k)) == -1) { for (List<Integer> ll : cs) { if (cmp(cs.get(k), ll) == -1 && cmp(ll, cs.get(i)) == -1) { res.add(List.of(cs.get(i), cs.get(j), cs.get(k), ll)); } } } } } } } return res; } public static void main(String[] args) { List<List<Integer>> combos = fourFaceCombos(); System.out.printf("Number of eligible 4-faced dice: %d%n", combos.size()); System.out.println(); List<List<List<Integer>>> it3 = findIntransitive3(combos); System.out.printf("%d ordered lists of 3 non-transitive dice found, namely:%n", it3.size()); for (List<List<Integer>> a : it3) { System.out.println(a); } System.out.println(); List<List<List<Integer>>> it4 = findIntransitive4(combos); System.out.printf("%d ordered lists of 4 non-transitive dice found, namely:%n", it4.size()); for (List<List<Integer>> a : it4) { System.out.println(a); } } }
Port the provided Go code into Java while preserving the original functionality.
package main import ( "fmt" "sort" "sync" "time" ) type history struct { timestamp tsFunc hs []hset } type tsFunc func() time.Time type hset struct { int t time.Time } func newHistory(ts tsFunc) history { return history{ts, []hset{{t: ts()}}} } func (h history) int() int { return h.hs[len(h.hs)-1].int } func (h *history) set(x int) time.Time { t := h.timestamp() h.hs = append(h.hs, hset{x, t}) return t } func (h history) dump() { for _, hs := range h.hs { fmt.Println(hs.t.Format(time.StampNano), hs.int) } } func (h history) recall(t time.Time) (int, bool) { i := sort.Search(len(h.hs), func(i int) bool { return h.hs[i].t.After(t) }) if i > 0 { return h.hs[i-1].int, true } return 0, false } func newTimestamper() tsFunc { var last time.Time return func() time.Time { if t := time.Now(); t.After(last) { last = t } else { last.Add(1) } return last } } func newProtectedTimestamper() tsFunc { var last time.Time var m sync.Mutex return func() (t time.Time) { t = time.Now() m.Lock() if t.After(last) { last = t } else { last.Add(1) t = last } m.Unlock() return } } func main() { ts := newTimestamper() h := newHistory(ts) ref := []time.Time{h.set(3), h.set(1), h.set(4)} fmt.Println("History of variable h:") h.dump() fmt.Println("Recalling values:") for _, t := range ref { rv, _ := h.recall(t) fmt.Println(rv) } }
public class HistoryVariable { private Object value; public HistoryVariable(Object v) { value = v; } public void update(Object v) { value = v; } public Object undo() { return value; } @Override public String toString() { return value.toString(); } public void dispose() { } }
Please provide an equivalent version of this Go code in Java.
package main import ( "github.com/fogleman/gg" "math/rand" "time" ) const c = 0.00001 func linear(x float64) float64 { return x*0.7 + 40 } type trainer struct { inputs []float64 answer int } func newTrainer(x, y float64, a int) *trainer { return &trainer{[]float64{x, y, 1}, a} } type perceptron struct { weights []float64 training []*trainer } func newPerceptron(n, w, h int) *perceptron { weights := make([]float64, n) for i := 0; i < n; i++ { weights[i] = rand.Float64()*2 - 1 } training := make([]*trainer, 2000) for i := 0; i < 2000; i++ { x := rand.Float64() * float64(w) y := rand.Float64() * float64(h) answer := 1 if y < linear(x) { answer = -1 } training[i] = newTrainer(x, y, answer) } return &perceptron{weights, training} } func (p *perceptron) feedForward(inputs []float64) int { if len(inputs) != len(p.weights) { panic("weights and input length mismatch, program terminated") } sum := 0.0 for i, w := range p.weights { sum += inputs[i] * w } if sum > 0 { return 1 } return -1 } func (p *perceptron) train(inputs []float64, desired int) { guess := p.feedForward(inputs) err := float64(desired - guess) for i := range p.weights { p.weights[i] += c * err * inputs[i] } } func (p *perceptron) draw(dc *gg.Context, iterations int) { le := len(p.training) for i, count := 0, 0; i < iterations; i, count = i+1, (count+1)%le { p.train(p.training[count].inputs, p.training[count].answer) } x := float64(dc.Width()) y := linear(x) dc.SetLineWidth(2) dc.SetRGB255(0, 0, 0) dc.DrawLine(0, linear(0), x, y) dc.Stroke() dc.SetLineWidth(1) for i := 0; i < le; i++ { guess := p.feedForward(p.training[i].inputs) x := p.training[i].inputs[0] - 4 y := p.training[i].inputs[1] - 4 if guess > 0 { dc.SetRGB(0, 0, 1) } else { dc.SetRGB(1, 0, 0) } dc.DrawCircle(x, y, 8) dc.Stroke() } } func main() { rand.Seed(time.Now().UnixNano()) w, h := 640, 360 perc := newPerceptron(3, w, h) dc := gg.NewContext(w, h) dc.SetRGB(1, 1, 1) dc.Clear() perc.draw(dc, 2000) dc.SavePNG("perceptron.png") }
import java.awt.*; import java.awt.event.ActionEvent; import java.util.*; import javax.swing.*; import javax.swing.Timer; public class Perceptron extends JPanel { class Trainer { double[] inputs; int answer; Trainer(double x, double y, int a) { inputs = new double[]{x, y, 1}; answer = a; } } Trainer[] training = new Trainer[2000]; double[] weights; double c = 0.00001; int count; public Perceptron(int n) { Random r = new Random(); Dimension dim = new Dimension(640, 360); setPreferredSize(dim); setBackground(Color.white); weights = new double[n]; for (int i = 0; i < weights.length; i++) { weights[i] = r.nextDouble() * 2 - 1; } for (int i = 0; i < training.length; i++) { double x = r.nextDouble() * dim.width; double y = r.nextDouble() * dim.height; int answer = y < f(x) ? -1 : 1; training[i] = new Trainer(x, y, answer); } new Timer(10, (ActionEvent e) -> { repaint(); }).start(); } private double f(double x) { return x * 0.7 + 40; } int feedForward(double[] inputs) { assert inputs.length == weights.length : "weights and input length mismatch"; double sum = 0; for (int i = 0; i < weights.length; i++) { sum += inputs[i] * weights[i]; } return activate(sum); } int activate(double s) { return s > 0 ? 1 : -1; } void train(double[] inputs, int desired) { int guess = feedForward(inputs); double error = desired - guess; for (int i = 0; i < weights.length; i++) { weights[i] += c * error * inputs[i]; } } @Override public void paintComponent(Graphics gg) { super.paintComponent(gg); Graphics2D g = (Graphics2D) gg; g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); int x = getWidth(); int y = (int) f(x); g.setStroke(new BasicStroke(2)); g.setColor(Color.orange); g.drawLine(0, (int) f(0), x, y); train(training[count].inputs, training[count].answer); count = (count + 1) % training.length; g.setStroke(new BasicStroke(1)); g.setColor(Color.black); for (int i = 0; i < count; i++) { int guess = feedForward(training[i].inputs); x = (int) training[i].inputs[0] - 4; y = (int) training[i].inputs[1] - 4; if (guess > 0) g.drawOval(x, y, 8, 8); else g.fillOval(x, y, 8, 8); } } public static void main(String[] args) { SwingUtilities.invokeLater(() -> { JFrame f = new JFrame(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setTitle("Perceptron"); f.setResizable(false); f.add(new Perceptron(3), BorderLayout.CENTER); f.pack(); f.setLocationRelativeTo(null); f.setVisible(true); }); } }
Translate the given Go code snippet into Java without altering its behavior.
package main import ( "fmt" "bitbucket.org/binet/go-eval/pkg/eval" "go/token" ) func main() { w := eval.NewWorld(); fset := token.NewFileSet(); code, err := w.Compile(fset, "1 + 2") if err != nil { fmt.Println("Compile error"); return } val, err := code.Run(); if err != nil { fmt.Println("Run time error"); return; } fmt.Println("Return value:", val) }
import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.OutputStream; import java.lang.reflect.InvocationTargetException; import java.net.URI; import java.util.HashMap; import java.util.LinkedList; import java.util.List; import java.util.Map; import javax.tools.FileObject; import javax.tools.ForwardingJavaFileManager; import javax.tools.JavaCompiler; import javax.tools.JavaFileObject; import javax.tools.SimpleJavaFileObject; import javax.tools.StandardJavaFileManager; import javax.tools.StandardLocation; import javax.tools.ToolProvider; public class Evaluator{ public static void main(String[] args){ new Evaluator().eval( "SayHello", "public class SayHello{public void speak(){System.out.println(\"Hello world\");}}", "speak" ); } void eval(String className, String classCode, String methodName){ Map<String, ByteArrayOutputStream> classCache = new HashMap<>(); JavaCompiler compiler = ToolProvider.getSystemJavaCompiler(); if ( null == compiler ) throw new RuntimeException("Could not get a compiler."); StandardJavaFileManager sfm = compiler.getStandardFileManager(null, null, null); ForwardingJavaFileManager<StandardJavaFileManager> fjfm = new ForwardingJavaFileManager<StandardJavaFileManager>(sfm){ @Override public JavaFileObject getJavaFileForOutput(Location location, String className, JavaFileObject.Kind kind, FileObject sibling) throws IOException{ if (StandardLocation.CLASS_OUTPUT == location && JavaFileObject.Kind.CLASS == kind) return new SimpleJavaFileObject(URI.create("mem: @Override public OutputStream openOutputStream() throws IOException{ ByteArrayOutputStream baos = new ByteArrayOutputStream(); classCache.put(className, baos); return baos; } }; else throw new IllegalArgumentException("Unexpected output file requested: " + location + ", " + className + ", " + kind); } }; List<JavaFileObject> files = new LinkedList<JavaFileObject>(){{ add( new SimpleJavaFileObject(URI.create("string: @Override public CharSequence getCharContent(boolean ignoreEncodingErrors){ return classCode; } } ); }}; compiler.getTask(null, fjfm, null, null, null, files).call(); try{ Class<?> clarse = new ClassLoader(){ @Override public Class<?> findClass(String name){ if (! name.startsWith(className)) throw new IllegalArgumentException("This class loader is for " + className + " - could not handle \"" + name + '"'); byte[] bytes = classCache.get(name).toByteArray(); return defineClass(name, bytes, 0, bytes.length); } }.loadClass(className); clarse.getMethod(methodName).invoke(clarse.newInstance()); }catch(ClassNotFoundException | InstantiationException | IllegalAccessException | NoSuchMethodException | InvocationTargetException x){ throw new RuntimeException("Run failed: " + x, x); } } }
Write a version of this Go function in Java with identical behavior.
package main import ( "fmt" "bitbucket.org/binet/go-eval/pkg/eval" "go/token" ) func main() { w := eval.NewWorld(); fset := token.NewFileSet(); code, err := w.Compile(fset, "1 + 2") if err != nil { fmt.Println("Compile error"); return } val, err := code.Run(); if err != nil { fmt.Println("Run time error"); return; } fmt.Println("Return value:", val) }
import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.OutputStream; import java.lang.reflect.InvocationTargetException; import java.net.URI; import java.util.HashMap; import java.util.LinkedList; import java.util.List; import java.util.Map; import javax.tools.FileObject; import javax.tools.ForwardingJavaFileManager; import javax.tools.JavaCompiler; import javax.tools.JavaFileObject; import javax.tools.SimpleJavaFileObject; import javax.tools.StandardJavaFileManager; import javax.tools.StandardLocation; import javax.tools.ToolProvider; public class Evaluator{ public static void main(String[] args){ new Evaluator().eval( "SayHello", "public class SayHello{public void speak(){System.out.println(\"Hello world\");}}", "speak" ); } void eval(String className, String classCode, String methodName){ Map<String, ByteArrayOutputStream> classCache = new HashMap<>(); JavaCompiler compiler = ToolProvider.getSystemJavaCompiler(); if ( null == compiler ) throw new RuntimeException("Could not get a compiler."); StandardJavaFileManager sfm = compiler.getStandardFileManager(null, null, null); ForwardingJavaFileManager<StandardJavaFileManager> fjfm = new ForwardingJavaFileManager<StandardJavaFileManager>(sfm){ @Override public JavaFileObject getJavaFileForOutput(Location location, String className, JavaFileObject.Kind kind, FileObject sibling) throws IOException{ if (StandardLocation.CLASS_OUTPUT == location && JavaFileObject.Kind.CLASS == kind) return new SimpleJavaFileObject(URI.create("mem: @Override public OutputStream openOutputStream() throws IOException{ ByteArrayOutputStream baos = new ByteArrayOutputStream(); classCache.put(className, baos); return baos; } }; else throw new IllegalArgumentException("Unexpected output file requested: " + location + ", " + className + ", " + kind); } }; List<JavaFileObject> files = new LinkedList<JavaFileObject>(){{ add( new SimpleJavaFileObject(URI.create("string: @Override public CharSequence getCharContent(boolean ignoreEncodingErrors){ return classCode; } } ); }}; compiler.getTask(null, fjfm, null, null, null, files).call(); try{ Class<?> clarse = new ClassLoader(){ @Override public Class<?> findClass(String name){ if (! name.startsWith(className)) throw new IllegalArgumentException("This class loader is for " + className + " - could not handle \"" + name + '"'); byte[] bytes = classCache.get(name).toByteArray(); return defineClass(name, bytes, 0, bytes.length); } }.loadClass(className); clarse.getMethod(methodName).invoke(clarse.newInstance()); }catch(ClassNotFoundException | InstantiationException | IllegalAccessException | NoSuchMethodException | InvocationTargetException x){ throw new RuntimeException("Run failed: " + x, x); } } }
Ensure the translated Java code behaves exactly like the original Go snippet.
package main import "fmt" func gcd(a, b uint) uint { if b == 0 { return a } return gcd(b, a%b) } func lcm(a, b uint) uint { return a / gcd(a, b) * b } func ipow(x, p uint) uint { prod := uint(1) for p > 0 { if p&1 != 0 { prod *= x } p >>= 1 x *= x } return prod } func getPrimes(n uint) []uint { var primes []uint for i := uint(2); i <= n; i++ { div := n / i mod := n % i for mod == 0 { primes = append(primes, i) n = div div = n / i mod = n % i } } return primes } func isPrime(n uint) bool { switch { case n < 2: return false case n%2 == 0: return n == 2 case n%3 == 0: return n == 3 default: d := uint(5) for d*d <= n { if n%d == 0 { return false } d += 2 if n%d == 0 { return false } d += 4 } return true } } func pisanoPeriod(m uint) uint { var p, c uint = 0, 1 for i := uint(0); i < m*m; i++ { p, c = c, (p+c)%m if p == 0 && c == 1 { return i + 1 } } return 1 } func pisanoPrime(p uint, k uint) uint { if !isPrime(p) || k == 0 { return 0 } return ipow(p, k-1) * pisanoPeriod(p) } func pisano(m uint) uint { primes := getPrimes(m) primePowers := make(map[uint]uint) for _, p := range primes { primePowers[p]++ } var pps []uint for k, v := range primePowers { pps = append(pps, pisanoPrime(k, v)) } if len(pps) == 0 { return 1 } if len(pps) == 1 { return pps[0] } f := pps[0] for i := 1; i < len(pps); i++ { f = lcm(f, pps[i]) } return f } func main() { for p := uint(2); p < 15; p++ { pp := pisanoPrime(p, 2) if pp > 0 { fmt.Printf("pisanoPrime(%2d: 2) = %d\n", p, pp) } } fmt.Println() for p := uint(2); p < 180; p++ { pp := pisanoPrime(p, 1) if pp > 0 { fmt.Printf("pisanoPrime(%3d: 1) = %d\n", p, pp) } } fmt.Println() fmt.Println("pisano(n) for integers 'n' from 1 to 180 are:") for n := uint(1); n <= 180; n++ { fmt.Printf("%3d ", pisano(n)) if n != 1 && n%15 == 0 { fmt.Println() } } fmt.Println() }
import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.TreeMap; public class PisanoPeriod { public static void main(String[] args) { System.out.printf("Print pisano(p^2) for every prime p lower than 15%n"); for ( long i = 2 ; i < 15 ; i++ ) { if ( isPrime(i) ) { long n = i*i; System.out.printf("pisano(%d) = %d%n", n, pisano(n)); } } System.out.printf("%nPrint pisano(p) for every prime p lower than 180%n"); for ( long n = 2 ; n < 180 ; n++ ) { if ( isPrime(n) ) { System.out.printf("pisano(%d) = %d%n", n, pisano(n)); } } System.out.printf("%nPrint pisano(n) for every integer from 1 to 180%n"); for ( long n = 1 ; n <= 180 ; n++ ) { System.out.printf("%3d ", pisano(n)); if ( n % 10 == 0 ) { System.out.printf("%n"); } } } private static final boolean isPrime(long test) { if ( test == 2 ) { return true; } if ( test % 2 == 0 ) { return false; } for ( long i = 3 ; i <= Math.sqrt(test) ; i += 2 ) { if ( test % i == 0 ) { return false; } } return true; } private static Map<Long,Long> PERIOD_MEMO = new HashMap<>(); static { PERIOD_MEMO.put(2L, 3L); PERIOD_MEMO.put(3L, 8L); PERIOD_MEMO.put(5L, 20L); } private static long pisano(long n) { if ( PERIOD_MEMO.containsKey(n) ) { return PERIOD_MEMO.get(n); } if ( n == 1 ) { return 1; } Map<Long,Long> factors = getFactors(n); if ( factors.size() == 1 & factors.get(2L) != null && factors.get(2L) > 0 ) { long result = 3 * n / 2; PERIOD_MEMO.put(n, result); return result; } if ( factors.size() == 1 & factors.get(5L) != null && factors.get(5L) > 0 ) { long result = 4*n; PERIOD_MEMO.put(n, result); return result; } if ( factors.size() == 2 & factors.get(2L) != null && factors.get(2L) == 1 && factors.get(5L) != null && factors.get(5L) > 0 ) { long result = 6*n; PERIOD_MEMO.put(n, result); return result; } List<Long> primes = new ArrayList<>(factors.keySet()); long prime = primes.get(0); if ( factors.size() == 1 && factors.get(prime) == 1 ) { List<Long> divisors = new ArrayList<>(); if ( n % 10 == 1 || n % 10 == 9 ) { for ( long divisor : getDivisors(prime-1) ) { if ( divisor % 2 == 0 ) { divisors.add(divisor); } } } else { List<Long> pPlus1Divisors = getDivisors(prime+1); for ( long divisor : getDivisors(2*prime+2) ) { if ( ! pPlus1Divisors.contains(divisor) ) { divisors.add(divisor); } } } Collections.sort(divisors); for ( long divisor : divisors ) { if ( fibModIdentity(divisor, prime) ) { PERIOD_MEMO.put(prime, divisor); return divisor; } } throw new RuntimeException("ERROR 144: Divisor not found."); } long period = (long) Math.pow(prime, factors.get(prime)-1) * pisano(prime); for ( int i = 1 ; i < primes.size() ; i++ ) { prime = primes.get(i); period = lcm(period, (long) Math.pow(prime, factors.get(prime)-1) * pisano(prime)); } PERIOD_MEMO.put(n, period); return period; } private static boolean fibModIdentity(long n, long mod) { long aRes = 0; long bRes = 1; long cRes = 1; long aBase = 0; long bBase = 1; long cBase = 1; while ( n > 0 ) { if ( n % 2 == 1 ) { long temp1 = 0, temp2 = 0, temp3 = 0; if ( aRes > SQRT || aBase > SQRT || bRes > SQRT || bBase > SQRT || cBase > SQRT || cRes > SQRT ) { temp1 = (multiply(aRes, aBase, mod) + multiply(bRes, bBase, mod)) % mod; temp2 = (multiply(aBase, bRes, mod) + multiply(bBase, cRes, mod)) % mod; temp3 = (multiply(bBase, bRes, mod) + multiply(cBase, cRes, mod)) % mod; } else { temp1 = ((aRes*aBase % mod) + (bRes*bBase % mod)) % mod; temp2 = ((aBase*bRes % mod) + (bBase*cRes % mod)) % mod; temp3 = ((bBase*bRes % mod) + (cBase*cRes % mod)) % mod; } aRes = temp1; bRes = temp2; cRes = temp3; } n >>= 1L; long temp1 = 0, temp2 = 0, temp3 = 0; if ( aBase > SQRT || bBase > SQRT || cBase > SQRT ) { temp1 = (multiply(aBase, aBase, mod) + multiply(bBase, bBase, mod)) % mod; temp2 = (multiply(aBase, bBase, mod) + multiply(bBase, cBase, mod)) % mod; temp3 = (multiply(bBase, bBase, mod) + multiply(cBase, cBase, mod)) % mod; } else { temp1 = ((aBase*aBase % mod) + (bBase*bBase % mod)) % mod; temp2 = ((aBase*bBase % mod) + (bBase*cBase % mod)) % mod; temp3 = ((bBase*bBase % mod) + (cBase*cBase % mod)) % mod; } aBase = temp1; bBase = temp2; cBase = temp3; } return aRes % mod == 0 && bRes % mod == 1 && cRes % mod == 1; } private static final long SQRT = (long) Math.sqrt(Long.MAX_VALUE); public static final long multiply(long a, long b, long modulus) { long x = 0; long y = a % modulus; long t; while ( b > 0 ) { if ( b % 2 == 1 ) { t = x + y; x = (t > modulus ? t-modulus : t); } t = y << 1; y = (t > modulus ? t-modulus : t); b >>= 1; } return x % modulus; } private static final List<Long> getDivisors(long number) { List<Long> divisors = new ArrayList<>(); long sqrt = (long) Math.sqrt(number); for ( long i = 1 ; i <= sqrt ; i++ ) { if ( number % i == 0 ) { divisors.add(i); long div = number / i; if ( div != i ) { divisors.add(div); } } } return divisors; } public static long lcm(long a, long b) { return a*b/gcd(a,b); } public static long gcd(long a, long b) { if ( b == 0 ) { return a; } return gcd(b, a%b); } private static final Map<Long,Map<Long,Long>> allFactors = new TreeMap<Long,Map<Long,Long>>(); static { Map<Long,Long> factors = new TreeMap<Long,Long>(); factors.put(2L, 1L); allFactors.put(2L, factors); } public static Long MAX_ALL_FACTORS = 100000L; public static final Map<Long,Long> getFactors(Long number) { if ( allFactors.containsKey(number) ) { return allFactors.get(number); } Map<Long,Long> factors = new TreeMap<Long,Long>(); if ( number % 2 == 0 ) { Map<Long,Long> factorsdDivTwo = getFactors(number/2); factors.putAll(factorsdDivTwo); factors.merge(2L, 1L, (v1, v2) -> v1 + v2); if ( number < MAX_ALL_FACTORS ) { allFactors.put(number, factors); } return factors; } boolean prime = true; long sqrt = (long) Math.sqrt(number); for ( long i = 3 ; i <= sqrt ; i += 2 ) { if ( number % i == 0 ) { prime = false; factors.putAll(getFactors(number/i)); factors.merge(i, 1L, (v1, v2) -> v1 + v2); if ( number < MAX_ALL_FACTORS ) { allFactors.put(number, factors); } return factors; } } if ( prime ) { factors.put(number, 1L); if ( number < MAX_ALL_FACTORS ) { allFactors.put(number, factors); } } return factors; } }
Produce a functionally identical Java code for the snippet given in Go.
package main import "fmt" const ( right = 1 left = -1 straight = 0 ) func normalize(tracks []int) string { size := len(tracks) a := make([]byte, size) for i := 0; i < size; i++ { a[i] = "abc"[tracks[i]+1] } norm := string(a) for i := 0; i < size; i++ { s := string(a) if s < norm { norm = s } tmp := a[0] copy(a, a[1:]) a[size-1] = tmp } return norm } func fullCircleStraight(tracks []int, nStraight int) bool { if nStraight == 0 { return true } count := 0 for _, track := range tracks { if track == straight { count++ } } if count != nStraight { return false } var straightTracks [12]int for i, idx := 0, 0; i < len(tracks) && idx >= 0; i++ { if tracks[i] == straight { straightTracks[idx%12]++ } idx += tracks[i] } any1, any2 := false, false for i := 0; i <= 5; i++ { if straightTracks[i] != straightTracks[i+6] { any1 = true break } } for i := 0; i <= 7; i++ { if straightTracks[i] != straightTracks[i+4] { any2 = true break } } return !any1 || !any2 } func fullCircleRight(tracks []int) bool { sum := 0 for _, track := range tracks { sum += track * 30 } if sum%360 != 0 { return false } var rTurns [12]int for i, idx := 0, 0; i < len(tracks) && idx >= 0; i++ { if tracks[i] == right { rTurns[idx%12]++ } idx += tracks[i] } any1, any2 := false, false for i := 0; i <= 5; i++ { if rTurns[i] != rTurns[i+6] { any1 = true break } } for i := 0; i <= 7; i++ { if rTurns[i] != rTurns[i+4] { any2 = true break } } return !any1 || !any2 } func circuits(nCurved, nStraight int) { solutions := make(map[string][]int) gen := getPermutationsGen(nCurved, nStraight) for gen.hasNext() { tracks := gen.next() if !fullCircleStraight(tracks, nStraight) { continue } if !fullCircleRight(tracks) { continue } tracks2 := make([]int, len(tracks)) copy(tracks2, tracks) solutions[normalize(tracks)] = tracks2 } report(solutions, nCurved, nStraight) } func getPermutationsGen(nCurved, nStraight int) PermutationsGen { if (nCurved+nStraight-12)%4 != 0 { panic("input must be 12 + k * 4") } var trackTypes []int switch nStraight { case 0: trackTypes = []int{right, left} case 12: trackTypes = []int{right, straight} default: trackTypes = []int{right, left, straight} } return NewPermutationsGen(nCurved+nStraight, trackTypes) } func report(sol map[string][]int, numC, numS int) { size := len(sol) fmt.Printf("\n%d solution(s) for C%d,%d \n", size, numC, numS) if numC <= 20 { for _, tracks := range sol { for _, track := range tracks { fmt.Printf("%2d ", track) } fmt.Println() } } } type PermutationsGen struct { NumPositions int choices []int indices []int sequence []int carry int } func NewPermutationsGen(numPositions int, choices []int) PermutationsGen { indices := make([]int, numPositions) sequence := make([]int, numPositions) carry := 0 return PermutationsGen{numPositions, choices, indices, sequence, carry} } func (p *PermutationsGen) next() []int { p.carry = 1 for i := 1; i < len(p.indices) && p.carry > 0; i++ { p.indices[i] += p.carry p.carry = 0 if p.indices[i] == len(p.choices) { p.carry = 1 p.indices[i] = 0 } } for j := 0; j < len(p.indices); j++ { p.sequence[j] = p.choices[p.indices[j]] } return p.sequence } func (p *PermutationsGen) hasNext() bool { return p.carry != 1 } func main() { for n := 12; n <= 28; n += 4 { circuits(n, 0) } circuits(12, 4) }
package railwaycircuit; import static java.util.Arrays.stream; import java.util.*; import static java.util.stream.IntStream.range; public class RailwayCircuit { final static int RIGHT = 1, LEFT = -1, STRAIGHT = 0; static String normalize(int[] tracks) { char[] a = new char[tracks.length]; for (int i = 0; i < a.length; i++) a[i] = "abc".charAt(tracks[i] + 1); String norm = new String(a); for (int i = 0, len = a.length; i < len; i++) { String s = new String(a); if (s.compareTo(norm) < 0) norm = s; char tmp = a[0]; for (int j = 1; j < a.length; j++) a[j - 1] = a[j]; a[len - 1] = tmp; } return norm; } static boolean fullCircleStraight(int[] tracks, int nStraight) { if (nStraight == 0) return true; if (stream(tracks).filter(i -> i == STRAIGHT).count() != nStraight) return false; int[] straight = new int[12]; for (int i = 0, idx = 0; i < tracks.length && idx >= 0; i++) { if (tracks[i] == STRAIGHT) straight[idx % 12]++; idx += tracks[i]; } return !(range(0, 6).anyMatch(i -> straight[i] != straight[i + 6]) && range(0, 8).anyMatch(i -> straight[i] != straight[i + 4])); } static boolean fullCircleRight(int[] tracks) { if (stream(tracks).map(i -> i * 30).sum() % 360 != 0) return false; int[] rTurns = new int[12]; for (int i = 0, idx = 0; i < tracks.length && idx >= 0; i++) { if (tracks[i] == RIGHT) rTurns[idx % 12]++; idx += tracks[i]; } return !(range(0, 6).anyMatch(i -> rTurns[i] != rTurns[i + 6]) && range(0, 8).anyMatch(i -> rTurns[i] != rTurns[i + 4])); } static void circuits(int nCurved, int nStraight) { Map<String, int[]> solutions = new HashMap<>(); PermutationsGen gen = getPermutationsGen(nCurved, nStraight); while (gen.hasNext()) { int[] tracks = gen.next(); if (!fullCircleStraight(tracks, nStraight)) continue; if (!fullCircleRight(tracks)) continue; solutions.put(normalize(tracks), tracks.clone()); } report(solutions, nCurved, nStraight); } static PermutationsGen getPermutationsGen(int nCurved, int nStraight) { assert (nCurved + nStraight - 12) % 4 == 0 : "input must be 12 + k * 4"; int[] trackTypes = new int[]{RIGHT, LEFT}; if (nStraight != 0) { if (nCurved == 12) trackTypes = new int[]{RIGHT, STRAIGHT}; else trackTypes = new int[]{RIGHT, LEFT, STRAIGHT}; } return new PermutationsGen(nCurved + nStraight, trackTypes); } static void report(Map<String, int[]> sol, int numC, int numS) { int size = sol.size(); System.out.printf("%n%d solution(s) for C%d,%d %n", size, numC, numS); if (size < 10) sol.values().stream().forEach(tracks -> { stream(tracks).forEach(i -> System.out.printf("%2d ", i)); System.out.println(); }); } public static void main(String[] args) { circuits(12, 0); circuits(16, 0); circuits(20, 0); circuits(24, 0); circuits(12, 4); } } class PermutationsGen { private int[] indices; private int[] choices; private int[] sequence; private int carry; PermutationsGen(int numPositions, int[] choices) { indices = new int[numPositions]; sequence = new int[numPositions]; this.choices = choices; } int[] next() { carry = 1; for (int i = 1; i < indices.length && carry > 0; i++) { indices[i] += carry; carry = 0; if (indices[i] == choices.length) { carry = 1; indices[i] = 0; } } for (int i = 0; i < indices.length; i++) sequence[i] = choices[indices[i]]; return sequence; } boolean hasNext() { return carry != 1; } }
Transform the following Go implementation into Java, maintaining the same output and logic.
package main import ( "fmt" "sort" ) type point struct{ x, y int } type polyomino []point type pointset map[point]bool func (p point) rotate90() point { return point{p.y, -p.x} } func (p point) rotate180() point { return point{-p.x, -p.y} } func (p point) rotate270() point { return point{-p.y, p.x} } func (p point) reflect() point { return point{-p.x, p.y} } func (p point) String() string { return fmt.Sprintf("(%d, %d)", p.x, p.y) } func (p point) contiguous() polyomino { return polyomino{point{p.x - 1, p.y}, point{p.x + 1, p.y}, point{p.x, p.y - 1}, point{p.x, p.y + 1}} } func (po polyomino) minima() (int, int) { minx := po[0].x miny := po[0].y for i := 1; i < len(po); i++ { if po[i].x < minx { minx = po[i].x } if po[i].y < miny { miny = po[i].y } } return minx, miny } func (po polyomino) translateToOrigin() polyomino { minx, miny := po.minima() res := make(polyomino, len(po)) for i, p := range po { res[i] = point{p.x - minx, p.y - miny} } sort.Slice(res, func(i, j int) bool { return res[i].x < res[j].x || (res[i].x == res[j].x && res[i].y < res[j].y) }) return res } func (po polyomino) rotationsAndReflections() []polyomino { rr := make([]polyomino, 8) for i := 0; i < 8; i++ { rr[i] = make(polyomino, len(po)) } copy(rr[0], po) for j := 0; j < len(po); j++ { rr[1][j] = po[j].rotate90() rr[2][j] = po[j].rotate180() rr[3][j] = po[j].rotate270() rr[4][j] = po[j].reflect() rr[5][j] = po[j].rotate90().reflect() rr[6][j] = po[j].rotate180().reflect() rr[7][j] = po[j].rotate270().reflect() } return rr } func (po polyomino) canonical() polyomino { rr := po.rotationsAndReflections() minr := rr[0].translateToOrigin() mins := minr.String() for i := 1; i < 8; i++ { r := rr[i].translateToOrigin() s := r.String() if s < mins { minr = r mins = s } } return minr } func (po polyomino) String() string { return fmt.Sprintf("%v", []point(po)) } func (po polyomino) toPointset() pointset { pset := make(pointset, len(po)) for _, p := range po { pset[p] = true } return pset } func (po polyomino) newPoints() polyomino { pset := po.toPointset() m := make(pointset) for _, p := range po { pts := p.contiguous() for _, pt := range pts { if !pset[pt] { m[pt] = true } } } poly := make(polyomino, 0, len(m)) for k := range m { poly = append(poly, k) } return poly } func (po polyomino) newPolys() []polyomino { pts := po.newPoints() res := make([]polyomino, len(pts)) for i, pt := range pts { poly := make(polyomino, len(po)) copy(poly, po) poly = append(poly, pt) res[i] = poly.canonical() } return res } var monomino = polyomino{point{0, 0}} var monominoes = []polyomino{monomino} func rank(n int) []polyomino { switch { case n < 0: panic("n cannot be negative. Program terminated.") case n == 0: return []polyomino{} case n == 1: return monominoes default: r := rank(n - 1) m := make(map[string]bool) var polys []polyomino for _, po := range r { for _, po2 := range po.newPolys() { if s := po2.String(); !m[s] { polys = append(polys, po2) m[s] = true } } } sort.Slice(polys, func(i, j int) bool { return polys[i].String() < polys[j].String() }) return polys } } func main() { const n = 5 fmt.Printf("All free polyominoes of rank %d:\n\n", n) for _, poly := range rank(n) { for _, pt := range poly { fmt.Printf("%s ", pt) } fmt.Println() } const k = 10 fmt.Printf("\nNumber of free polyominoes of ranks 1 to %d:\n", k) for i := 1; i <= k; i++ { fmt.Printf("%d ", len(rank(i))) } fmt.Println() }
import java.awt.Point; import java.util.*; import static java.util.Arrays.asList; import java.util.function.Function; import static java.util.Comparator.comparing; import static java.util.stream.Collectors.toList; public class FreePolyominoesEnum { static final List<Function<Point, Point>> transforms = new ArrayList<>(); static { transforms.add(p -> new Point(p.y, -p.x)); transforms.add(p -> new Point(-p.x, -p.y)); transforms.add(p -> new Point(-p.y, p.x)); transforms.add(p -> new Point(-p.x, p.y)); transforms.add(p -> new Point(-p.y, -p.x)); transforms.add(p -> new Point(p.x, -p.y)); transforms.add(p -> new Point(p.y, p.x)); } static Point findMinima(List<Point> poly) { return new Point( poly.stream().mapToInt(a -> a.x).min().getAsInt(), poly.stream().mapToInt(a -> a.y).min().getAsInt()); } static List<Point> translateToOrigin(List<Point> poly) { final Point min = findMinima(poly); poly.replaceAll(p -> new Point(p.x - min.x, p.y - min.y)); return poly; } static List<List<Point>> rotationsAndReflections(List<Point> poly) { List<List<Point>> lst = new ArrayList<>(); lst.add(poly); for (Function<Point, Point> t : transforms) lst.add(poly.stream().map(t).collect(toList())); return lst; } static Comparator<Point> byCoords = Comparator.<Point>comparingInt(p -> p.x) .thenComparingInt(p -> p.y); static List<Point> normalize(List<Point> poly) { return rotationsAndReflections(poly).stream() .map(lst -> translateToOrigin(lst)) .map(lst -> lst.stream().sorted(byCoords).collect(toList())) .min(comparing(Object::toString)) .get(); } static List<Point> neighborhoods(Point p) { return asList(new Point(p.x - 1, p.y), new Point(p.x + 1, p.y), new Point(p.x, p.y - 1), new Point(p.x, p.y + 1)); } static List<Point> concat(List<Point> lst, Point pt) { List<Point> r = new ArrayList<>(); r.addAll(lst); r.add(pt); return r; } static List<Point> newPoints(List<Point> poly) { return poly.stream() .flatMap(p -> neighborhoods(p).stream()) .filter(p -> !poly.contains(p)) .distinct() .collect(toList()); } static List<List<Point>> constructNextRank(List<Point> poly) { return newPoints(poly).stream() .map(p -> normalize(concat(poly, p))) .distinct() .collect(toList()); } static List<List<Point>> rank(int n) { if (n < 0) throw new IllegalArgumentException("n cannot be negative"); if (n < 2) { List<List<Point>> r = new ArrayList<>(); if (n == 1) r.add(asList(new Point(0, 0))); return r; } return rank(n - 1).stream() .parallel() .flatMap(lst -> constructNextRank(lst).stream()) .distinct() .collect(toList()); } public static void main(String[] args) { for (List<Point> poly : rank(5)) { for (Point p : poly) System.out.printf("(%d,%d) ", p.x, p.y); System.out.println(); } } }
Can you help me rewrite this code in Java instead of Go, keeping it the same logically?
package main import ( "bytes" "encoding/json" "fmt" "io/ioutil" "log" "net/http" "net/url" "os" "strings" "time" ) var key string func init() { const keyFile = "api_key.txt" f, err := os.Open(keyFile) if err != nil { log.Fatal(err) } keydata, err := ioutil.ReadAll(f) if err != nil { log.Fatal(err) } key = strings.TrimSpace(string(keydata)) } type EventResponse struct { Results []Result } type Result struct { ID string Status string Name string EventURL string `json:"event_url"` Description string Time EventTime } type EventTime struct{ time.Time } func (et *EventTime) UnmarshalJSON(data []byte) error { var msec int64 if err := json.Unmarshal(data, &msec); err != nil { return err } et.Time = time.Unix(0, msec*int64(time.Millisecond)) return nil } func (et EventTime) MarshalJSON() ([]byte, error) { msec := et.UnixNano() / int64(time.Millisecond) return json.Marshal(msec) } func (r *Result) String() string { var b bytes.Buffer fmt.Fprintln(&b, "ID:", r.ID) fmt.Fprintln(&b, "URL:", r.EventURL) fmt.Fprintln(&b, "Time:", r.Time.Format(time.UnixDate)) d := r.Description const limit = 65 if len(d) > limit { d = d[:limit-1] + "…" } fmt.Fprintln(&b, "Description:", d) return b.String() } func main() { v := url.Values{ "topic": []string{"photo"}, "time": []string{",1w"}, "key": []string{key}, } u := url.URL{ Scheme: "http", Host: "api.meetup.com", Path: "2/open_events.json", RawQuery: v.Encode(), } resp, err := http.Get(u.String()) if err != nil { log.Fatal(err) } defer resp.Body.Close() log.Println("HTTP Status:", resp.Status) body, err := ioutil.ReadAll(resp.Body) if err != nil { log.Fatal(err) } var buf bytes.Buffer if err = json.Indent(&buf, body, "", " "); err != nil { log.Fatal(err) } var evresp EventResponse json.Unmarshal(body, &evresp) fmt.Println("Got", len(evresp.Results), "events") if len(evresp.Results) > 0 { fmt.Println("First event:\n", &evresp.Results[0]) } }
package src; import java.io.BufferedReader; import java.io.FileReader; import java.net.URI; import org.apache.http.client.methods.CloseableHttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.utils.URIBuilder; import org.apache.http.impl.client.CloseableHttpClient; import org.apache.http.impl.client.HttpClients; import org.apache.http.util.EntityUtils; public class EventGetter { String city = ""; String topic = ""; public String getEvent(String path_code,String key) throws Exception{ String responseString = ""; URI request = new URIBuilder() .setScheme("http") .setHost("api.meetup.com") .setPath(path_code) .setParameter("topic", topic) .setParameter("city", city) .setParameter("key", key) .build(); HttpGet get = new HttpGet(request); System.out.println("Get request : "+get.toString()); CloseableHttpClient client = HttpClients.createDefault(); CloseableHttpResponse response = client.execute(get); responseString = EntityUtils.toString(response.getEntity()); return responseString; } public String getApiKey(String key_path){ String key = ""; try{ BufferedReader reader = new BufferedReader(new FileReader(key_path)); key = reader.readLine().toString(); reader.close(); } catch(Exception e){System.out.println(e.toString());} return key; } }
Produce a functionally identical Java code for the snippet given in Go.
package main import "fmt" var solution = make(chan int) var nearMiss = make(chan int) var done = make(chan bool) func main() { for i := 0; i < 4096; i++ { go checkPerm(i) } var ms []int for i := 0; i < 4096; { select { case <-done: i++ case s := <-solution: print12("solution", s) case m := <-nearMiss: ms = append(ms, m) } } for _, m := range ms { print12("near miss", m) } } func print12(label string, bits int) { fmt.Print(label, ":") for i := 1; i <= 12; i++ { if bits&1 == 1 { fmt.Print(" ", i) } bits >>= 1 } fmt.Println() } func checkPerm(tz int) { ts := func(n uint) bool { return tz>>(n-1)&1 == 1 } ntrue := func(xs ...uint) int { nt := 0 for _, x := range xs { if ts(x) { nt++ } } return nt } var con bool test := func(statement uint, b bool) { switch { case ts(statement) == b: case con: panic("bail") default: con = true } } defer func() { if x := recover(); x != nil { if msg, ok := x.(string); !ok && msg != "bail" { panic(x) } } done <- true }() test(1, true) test(2, ntrue(7, 8, 9, 10, 11, 12) == 3) test(3, ntrue(2, 4, 6, 8, 10, 12) == 2) test(4, !ts(5) || ts(6) && ts(7)) test(5, !ts(4) && !ts(3) && !ts(2)) test(6, ntrue(1, 3, 5, 7, 9, 11) == 4) test(7, ts(2) != ts(3)) test(8, !ts(7) || ts(5) && ts(6)) test(9, ntrue(1, 2, 3, 4, 5, 6) == 3) test(10, ts(11) && ts(12)) test(11, ntrue(7, 8, 9) == 1) test(12, ntrue(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) == 4) if con { nearMiss <- tz } else { solution <- tz } }
public class LogicPuzzle { boolean S[] = new boolean[13]; int Count = 0; public boolean check2 () { int count = 0; for (int k = 7; k <= 12; k++) if (S[k]) count++; return S[2] == (count == 3); } public boolean check3 () { int count = 0; for (int k = 2; k <= 12; k += 2) if (S[k]) count++; return S[3] == (count == 2); } public boolean check4 () { return S[4] == ( !S[5] || S[6] && S[7]); } public boolean check5 () { return S[5] == ( !S[2] && !S[3] && !S[4]); } public boolean check6 () { int count = 0; for (int k = 1; k <= 11; k += 2) if (S[k]) count++; return S[6] == (count == 4); } public boolean check7 () { return S[7] == ((S[2] || S[3]) && !(S[2] && S[3])); } public boolean check8 () { return S[8] == ( !S[7] || S[5] && S[6]); } public boolean check9 () { int count = 0; for (int k = 1; k <= 6; k++) if (S[k]) count++; return S[9] == (count == 3); } public boolean check10 () { return S[10] == (S[11] && S[12]); } public boolean check11 () { int count = 0; for (int k = 7; k <= 9; k++) if (S[k]) count++; return S[11] == (count == 1); } public boolean check12 () { int count = 0; for (int k = 1; k <= 11; k++) if (S[k]) count++; return S[12] == (count == 4); } public void check () { if (check2() && check3() && check4() && check5() && check6() && check7() && check8() && check9() && check10() && check11() && check12()) { for (int k = 1; k <= 12; k++) if (S[k]) System.out.print(k + " "); System.out.println(); Count++; } } public void recurseAll (int k) { if (k == 13) check(); else { S[k] = false; recurseAll(k + 1); S[k] = true; recurseAll(k + 1); } } public static void main (String args[]) { LogicPuzzle P = new LogicPuzzle(); P.S[1] = true; P.recurseAll(2); System.out.println(); System.out.println(P.Count + " Solutions found."); } }
Keep all operations the same but rewrite the snippet in Java.
package main import "fmt" var solution = make(chan int) var nearMiss = make(chan int) var done = make(chan bool) func main() { for i := 0; i < 4096; i++ { go checkPerm(i) } var ms []int for i := 0; i < 4096; { select { case <-done: i++ case s := <-solution: print12("solution", s) case m := <-nearMiss: ms = append(ms, m) } } for _, m := range ms { print12("near miss", m) } } func print12(label string, bits int) { fmt.Print(label, ":") for i := 1; i <= 12; i++ { if bits&1 == 1 { fmt.Print(" ", i) } bits >>= 1 } fmt.Println() } func checkPerm(tz int) { ts := func(n uint) bool { return tz>>(n-1)&1 == 1 } ntrue := func(xs ...uint) int { nt := 0 for _, x := range xs { if ts(x) { nt++ } } return nt } var con bool test := func(statement uint, b bool) { switch { case ts(statement) == b: case con: panic("bail") default: con = true } } defer func() { if x := recover(); x != nil { if msg, ok := x.(string); !ok && msg != "bail" { panic(x) } } done <- true }() test(1, true) test(2, ntrue(7, 8, 9, 10, 11, 12) == 3) test(3, ntrue(2, 4, 6, 8, 10, 12) == 2) test(4, !ts(5) || ts(6) && ts(7)) test(5, !ts(4) && !ts(3) && !ts(2)) test(6, ntrue(1, 3, 5, 7, 9, 11) == 4) test(7, ts(2) != ts(3)) test(8, !ts(7) || ts(5) && ts(6)) test(9, ntrue(1, 2, 3, 4, 5, 6) == 3) test(10, ts(11) && ts(12)) test(11, ntrue(7, 8, 9) == 1) test(12, ntrue(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) == 4) if con { nearMiss <- tz } else { solution <- tz } }
public class LogicPuzzle { boolean S[] = new boolean[13]; int Count = 0; public boolean check2 () { int count = 0; for (int k = 7; k <= 12; k++) if (S[k]) count++; return S[2] == (count == 3); } public boolean check3 () { int count = 0; for (int k = 2; k <= 12; k += 2) if (S[k]) count++; return S[3] == (count == 2); } public boolean check4 () { return S[4] == ( !S[5] || S[6] && S[7]); } public boolean check5 () { return S[5] == ( !S[2] && !S[3] && !S[4]); } public boolean check6 () { int count = 0; for (int k = 1; k <= 11; k += 2) if (S[k]) count++; return S[6] == (count == 4); } public boolean check7 () { return S[7] == ((S[2] || S[3]) && !(S[2] && S[3])); } public boolean check8 () { return S[8] == ( !S[7] || S[5] && S[6]); } public boolean check9 () { int count = 0; for (int k = 1; k <= 6; k++) if (S[k]) count++; return S[9] == (count == 3); } public boolean check10 () { return S[10] == (S[11] && S[12]); } public boolean check11 () { int count = 0; for (int k = 7; k <= 9; k++) if (S[k]) count++; return S[11] == (count == 1); } public boolean check12 () { int count = 0; for (int k = 1; k <= 11; k++) if (S[k]) count++; return S[12] == (count == 4); } public void check () { if (check2() && check3() && check4() && check5() && check6() && check7() && check8() && check9() && check10() && check11() && check12()) { for (int k = 1; k <= 12; k++) if (S[k]) System.out.print(k + " "); System.out.println(); Count++; } } public void recurseAll (int k) { if (k == 13) check(); else { S[k] = false; recurseAll(k + 1); S[k] = true; recurseAll(k + 1); } } public static void main (String args[]) { LogicPuzzle P = new LogicPuzzle(); P.S[1] = true; P.recurseAll(2); System.out.println(); System.out.println(P.Count + " Solutions found."); } }