Instruction
stringlengths
45
106
input_code
stringlengths
1
13.7k
output_code
stringlengths
1
13.7k
Generate a Ruby translation of this Java snippet without changing its computational steps.
public class Pancake { private static int pancake(int n) { int gap = 2; int sum = 2; int adj = -1; while (sum < n) { adj++; gap = 2 * gap - 1; sum += gap; } return n + adj; } public static void main(String[] args) { for (int i = 0; i < 4; i++) { for (int j = 1; j < 6; j++) { int n = 5 * i + j; System.out.printf("p(%2d) = %2d ", n, pancake(n)); } System.out.println(); } } }
def pancake(n) gap = 2 sum = 2 adj = -1 while sum < n adj = adj + 1 gap = gap * 2 - 1 sum = sum + gap end return n + adj end for i in 0 .. 3 for j in 1 .. 5 n = i * 5 + j print "p(%2d) = %2d " % [n, pancake(n)] end print "\n" end
Generate a Ruby translation of this Java snippet without changing its computational steps.
import java.util.ArrayList; import java.util.List; public class PythagoreanQuadruples { public static void main(String[] args) { long d = 2200; System.out.printf("Values of d < %d where a, b, and c are non-zero and a^2 + b^2 + c^2 = d^2 has no solutions:%n%s%n", d, getPythagoreanQuadruples(d)); } private static List<Long> getPythagoreanQuadruples(long max) { List<Long> list = new ArrayList<>(); long n = -1; long m = -1; while ( true ) { long nTest = (long) Math.pow(2, n+1); long mTest = (long) (5L * Math.pow(2, m+1)); long test = 0; if ( nTest > mTest ) { test = mTest; m++; } else { test = nTest; n++; } if ( test < max ) { list.add(test); } else { break; } } return list; } }
n = 2200 l_add, l = Hash(Int32, Bool).new(false), Hash(Int32, Bool).new(false) (1..n).each do |x| x2 = x * x (x..n).each { |y| l_add[x2 + y * y] = true } end s = 3 (1..n).each do |x| s1 = s s += 2 s2 = s ((x+1)..n).each do |y| l[y] = true if l_add[s1] s1 += s2 s2 += 2 end end puts (1..n).reject{ |x| l[x] }.join(" ")
Produce a functionally identical Ruby code for the snippet given in Java.
package org.rosettacode; import java.util.ArrayList; import java.util.List; public class SumAndProductPuzzle { private final long beginning; private final int maxSum; private static final int MIN_VALUE = 2; private List<int[]> firstConditionExcludes = new ArrayList<>(); private List<int[]> secondConditionExcludes = new ArrayList<>(); public static void main(String... args){ if (args.length == 0){ new SumAndProductPuzzle(100).run(); new SumAndProductPuzzle(1684).run(); new SumAndProductPuzzle(1685).run(); } else { for (String arg : args){ try{ new SumAndProductPuzzle(Integer.valueOf(arg)).run(); } catch (NumberFormatException e){ System.out.println("Please provide only integer arguments. " + "Provided argument " + arg + " was not an integer. " + "Alternatively, calling the program with no arguments " + "will run the puzzle where maximum sum equals 100, 1684, and 1865."); } } } } public SumAndProductPuzzle(int maxSum){ this.beginning = System.currentTimeMillis(); this.maxSum = maxSum; System.out.println("Run with maximum sum of " + String.valueOf(maxSum) + " started at " + String.valueOf(beginning) + "."); } public void run(){ for (int x = MIN_VALUE; x < maxSum - MIN_VALUE; x++){ for (int y = x + 1; y < maxSum - MIN_VALUE; y++){ if (isSumNoGreaterThanMax(x,y) && isSKnowsPCannotKnow(x,y) && isPKnowsNow(x,y) && isSKnowsNow(x,y) ){ System.out.println("Found solution x is " + String.valueOf(x) + " y is " + String.valueOf(y) + " in " + String.valueOf(System.currentTimeMillis() - beginning) + "ms."); } } } System.out.println("Run with maximum sum of " + String.valueOf(maxSum) + " ended in " + String.valueOf(System.currentTimeMillis() - beginning) + "ms."); } public boolean isSumNoGreaterThanMax(int x, int y){ return x + y <= maxSum; } public boolean isSKnowsPCannotKnow(int x, int y){ if (firstConditionExcludes.contains(new int[] {x, y})){ return false; } for (int[] addends : sumAddends(x, y)){ if ( !(productFactors(addends[0], addends[1]).size() > 1) ) { firstConditionExcludes.add(new int[] {x, y}); return false; } } return true; } public boolean isPKnowsNow(int x, int y){ if (secondConditionExcludes.contains(new int[] {x, y})){ return false; } int countSolutions = 0; for (int[] factors : productFactors(x, y)){ if (isSKnowsPCannotKnow(factors[0], factors[1])){ countSolutions++; } } if (countSolutions == 1){ return true; } else { secondConditionExcludes.add(new int[] {x, y}); return false; } } public boolean isSKnowsNow(int x, int y){ int countSolutions = 0; for (int[] addends : sumAddends(x, y)){ if (isPKnowsNow(addends[0], addends[1])){ countSolutions++; } } return countSolutions == 1; } public List<int[]> sumAddends(int x, int y){ List<int[]> list = new ArrayList<>(); int sum = x + y; for (int addend = MIN_VALUE; addend < sum - addend; addend++){ if (isSumNoGreaterThanMax(addend, sum - addend)){ list.add(new int[]{addend, sum - addend}); } } return list; } public List<int[]> productFactors(int x, int y){ List<int[]> list = new ArrayList<>(); int product = x * y; for (int factor = MIN_VALUE; factor < product / factor; factor++){ if (product % factor == 0){ if (isSumNoGreaterThanMax(factor, product / factor)){ list.add(new int[]{factor, product / factor}); } } } return list; } }
def add(x,y) x + y end def mul(x,y) x * y end def sumEq(s,p) s.select{|q| add(*p) == add(*q)} end def mulEq(s,p) s.select{|q| mul(*p) == mul(*q)} end s1 = (a = *2...100).product(a).select{|x,y| x<y && x+y<100} s2 = s1.select{|p| sumEq(s1,p).all?{|q| mulEq(s1,q).size != 1} } s3 = s2.select{|p| (mulEq(s1,p) & s2).size == 1} p s3.select{|p| (sumEq(s1,p) & s3).size == 1}
Produce a language-to-language conversion: from Java to Ruby, same semantics.
import static java.util.stream.IntStream.rangeClosed; public class Test { final static int nMax = 12; static char[] superperm; static int pos; static int[] count = new int[nMax]; static int factSum(int n) { return rangeClosed(1, n) .map(m -> rangeClosed(1, m).reduce(1, (a, b) -> a * b)).sum(); } static boolean r(int n) { if (n == 0) return false; char c = superperm[pos - n]; if (--count[n] == 0) { count[n] = n; if (!r(n - 1)) return false; } superperm[pos++] = c; return true; } static void superPerm(int n) { String chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"; pos = n; superperm = new char[factSum(n)]; for (int i = 0; i < n + 1; i++) count[i] = i; for (int i = 1; i < n + 1; i++) superperm[i - 1] = chars.charAt(i); while (r(n)) { } } public static void main(String[] args) { for (int n = 0; n < nMax; n++) { superPerm(n); System.out.printf("superPerm(%2d) len = %d", n, superperm.length); System.out.println(); } } }
l = [] (1..6).each{|e| a, i = [], e-2 (0..l.length-e+1).each{|g| if not (n = l[g..g+e-2]).uniq! a.concat(n[(a[0]? i : 0)..-1]).push(e).concat(n) i = e-2 else i -= 1 end } a.each{|n| print n}; puts "\n\n" l = a }
Produce a functionally identical Ruby code for the snippet given in Java.
import java.math.BigDecimal; import java.util.List; public class TestIntegerness { private static boolean isLong(double d) { return isLong(d, 0.0); } private static boolean isLong(double d, double tolerance) { return (d - Math.floor(d)) <= tolerance || (Math.ceil(d) - d) <= tolerance; } @SuppressWarnings("ResultOfMethodCallIgnored") private static boolean isBigInteger(BigDecimal bd) { try { bd.toBigIntegerExact(); return true; } catch (ArithmeticException ex) { return false; } } private static class Rational { long num; long denom; Rational(int num, int denom) { this.num = num; this.denom = denom; } boolean isLong() { return num % denom == 0; } @Override public String toString() { return String.format("%s/%s", num, denom); } } private static class Complex { double real; double imag; Complex(double real, double imag) { this.real = real; this.imag = imag; } boolean isLong() { return TestIntegerness.isLong(real) && imag == 0.0; } @Override public String toString() { if (imag >= 0.0) { return String.format("%s + %si", real, imag); } return String.format("%s - %si", real, imag); } } public static void main(String[] args) { List<Double> da = List.of(25.000000, 24.999999, 25.000100); for (Double d : da) { boolean exact = isLong(d); System.out.printf("%.6f is %s integer%n", d, exact ? "an" : "not an"); } System.out.println(); double tolerance = 0.00001; System.out.printf("With a tolerance of %.5f:%n", tolerance); for (Double d : da) { boolean fuzzy = isLong(d, tolerance); System.out.printf("%.6f is %s integer%n", d, fuzzy ? "an" : "not an"); } System.out.println(); List<Double> fa = List.of(-2.1e120, -5e-2, Double.NaN, Double.POSITIVE_INFINITY); for (Double f : fa) { boolean exact = !f.isNaN() && !f.isInfinite() && isBigInteger(new BigDecimal(f.toString())); System.out.printf("%s is %s integer%n", f, exact ? "an" : "not an"); } System.out.println(); List<Complex> ca = List.of(new Complex(5.0, 0.0), new Complex(5.0, -5.0)); for (Complex c : ca) { boolean exact = c.isLong(); System.out.printf("%s is %s integer%n", c, exact ? "an" : "not an"); } System.out.println(); List<Rational> ra = List.of(new Rational(24, 8), new Rational(-5, 1), new Rational(17, 2)); for (Rational r : ra) { boolean exact = r.isLong(); System.out.printf("%s is %s integer%n", r, exact ? "an" : "not an"); } } }
class Numeric def to_i? self == self.to_i rescue false end end ar = [25.000000, 24.999999, 25.000100, -2.1e120, -5e-2, Float::NAN, Float::INFINITY, 2r, 2.5r, 2+0i, 2+0.0i, 5-5i] ar.each{|num| puts "
Convert this Java snippet to Ruby and keep its semantics consistent.
public class UlamNumbers { public static void main(String[] args) { long start = System.currentTimeMillis(); for (int n = 1; n <= 100000; n *= 10) { System.out.printf("Ulam(%d) = %d\n", n, ulam(n)); } long finish = System.currentTimeMillis(); System.out.printf("Elapsed time: %.3f seconds\n", (finish - start)/1000.0); } private static int ulam(int n) { int[] ulams = new int[Math.max(n, 2)]; ulams[0] = 1; ulams[1] = 2; int sieveLength = 2; int[] sieve = new int[sieveLength]; sieve[0] = sieve[1] = 1; for (int u = 2, ulen = 2; ulen < n; ) { sieveLength = u + ulams[ulen - 2]; sieve = extend(sieve, sieveLength); for (int i = 0; i < ulen - 1; ++i) ++sieve[u + ulams[i] - 1]; for (int i = u; i < sieveLength; ++i) { if (sieve[i] == 1) { u = i + 1; ulams[ulen++] = u; break; } } } return ulams[n - 1]; } private static int[] extend(int[] array, int minLength) { if (minLength <= array.length) return array; int newLength = 2 * array.length; while (newLength < minLength) newLength *= 2; int[] newArray = new int[newLength]; System.arraycopy(array, 0, newArray, 0, array.length); return newArray; } }
func ulam(n) { static u = Set(1,2) static ulams = [0, 1, 2] return ulams[n] if (ulams.end >= n) ++n for(var i = 3; true; ++i) { var count = 0 ulams.each {|v| if (u.has(i - v) && (v != i-v)) { break if (count++ > 2) } } if (count == 2) { ulams << i u << i break if (ulams.len == n) } } ulams.tail } for k in (1..3) { say "The 10^ }
Write the same code in Ruby as shown below in Java.
public class TypeDetection { private static void showType(Object a) { if (a instanceof Integer) { System.out.printf("'%s' is an integer\n", a); } else if (a instanceof Double) { System.out.printf("'%s' is a double\n", a); } else if (a instanceof Character) { System.out.printf("'%s' is a character\n", a); } else { System.out.printf("'%s' is some other type\n", a); } } public static void main(String[] args) { showType(5); showType(7.5); showType('d'); showType(true); } }
def print_type(x) puts "Compile-time type of puts " Actual runtime type is end print_type 123 print_type 123.45 print_type rand < 0.5 ? "1" : 0 print_type rand < 1.5 print_type nil print_type 'c' print_type "str" print_type [1,2] print_type({ 2, "two" }) print_type({a: 1, b: 2}) print_type ->(x : Int32){ x+2 > 0 }
Write the same code in Ruby as shown below in Java.
public class SafePrimes { public static void main(String... args) { int SIEVE_SIZE = 10_000_000; boolean[] isComposite = new boolean[SIEVE_SIZE]; isComposite[0] = true; isComposite[1] = true; for (int n = 2; n < SIEVE_SIZE; n++) { if (isComposite[n]) { continue; } for (int i = n * 2; i < SIEVE_SIZE; i += n) { isComposite[i] = true; } } int oldSafePrimeCount = 0; int oldUnsafePrimeCount = 0; int safePrimeCount = 0; int unsafePrimeCount = 0; StringBuilder safePrimes = new StringBuilder(); StringBuilder unsafePrimes = new StringBuilder(); int safePrimesStrCount = 0; int unsafePrimesStrCount = 0; for (int n = 2; n < SIEVE_SIZE; n++) { if (n == 1_000_000) { oldSafePrimeCount = safePrimeCount; oldUnsafePrimeCount = unsafePrimeCount; } if (isComposite[n]) { continue; } boolean isUnsafe = isComposite[(n - 1) >>> 1]; if (isUnsafe) { if (unsafePrimeCount < 40) { if (unsafePrimeCount > 0) { unsafePrimes.append(", "); } unsafePrimes.append(n); unsafePrimesStrCount++; } unsafePrimeCount++; } else { if (safePrimeCount < 35) { if (safePrimeCount > 0) { safePrimes.append(", "); } safePrimes.append(n); safePrimesStrCount++; } safePrimeCount++; } } System.out.println("First " + safePrimesStrCount + " safe primes: " + safePrimes.toString()); System.out.println("Number of safe primes below 1,000,000: " + oldSafePrimeCount); System.out.println("Number of safe primes below 10,000,000: " + safePrimeCount); System.out.println("First " + unsafePrimesStrCount + " unsafe primes: " + unsafePrimes.toString()); System.out.println("Number of unsafe primes below 1,000,000: " + oldUnsafePrimeCount); System.out.println("Number of unsafe primes below 10,000,000: " + unsafePrimeCount); return; } }
require "prime" class Integer def safe_prime? ((self-1)/2).prime? end end def format_parts(n) partitions = Prime.each(n).partition(&:safe_prime?).map(&:count) "There are %d safes and %d unsafes below end puts "First 35 safe-primes:" p Prime.each.lazy.select(&:safe_prime?).take(35).to_a puts format_parts(1_000_000), "\n" puts "First 40 unsafe-primes:" p Prime.each.lazy.reject(&:safe_prime?).take(40).to_a puts format_parts(10_000_000)
Preserve the algorithm and functionality while converting the code from Java to Ruby.
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; } }
def hashJoin(table1, index1, table2, index2) h = table1.group_by {|s| s[index1]} h.default = [] table2.collect {|r| h[r[index2]].collect {|s| [s, r]} }.flatten(1) end table1 = [[27, "Jonah"], [18, "Alan"], [28, "Glory"], [18, "Popeye"], [28, "Alan"]] table2 = [["Jonah", "Whales"], ["Jonah", "Spiders"], ["Alan", "Ghosts"], ["Alan", "Zombies"], ["Glory", "Buffy"]] hashJoin(table1, 1, table2, 0).each { |row| p row }
Write the same algorithm in Ruby as shown in this Java implementation.
import java.util.function.Predicate; public class PermutationsWithRepetitions { public static void main(String[] args) { char[] chars = {'a', 'b', 'c', 'd'}; permute(chars, 3, i -> i[0] == 1 && i[1] == 1 && i[2] == 0); } static void permute(char[] a, int k, Predicate<int[]> decider) { int n = a.length; if (k < 1 || k > n) throw new IllegalArgumentException("Illegal number of positions."); int[] indexes = new int[n]; int total = (int) Math.pow(n, k); while (total-- > 0) { for (int i = 0; i < n - (n - k); i++) System.out.print(a[indexes[i]]); System.out.println(); if (decider.test(indexes)) break; for (int i = 0; i < n; i++) { if (indexes[i] >= n - 1) { indexes[i] = 0; } else { indexes[i]++; break; } } } } }
rp = [1,2,3].repeated_permutation(2) p rp.to_a p rp.take_while{|(a, b)| a + b < 5}
Convert this Java snippet to Ruby and keep its semantics consistent.
import java.util.function.Predicate; public class PermutationsWithRepetitions { public static void main(String[] args) { char[] chars = {'a', 'b', 'c', 'd'}; permute(chars, 3, i -> i[0] == 1 && i[1] == 1 && i[2] == 0); } static void permute(char[] a, int k, Predicate<int[]> decider) { int n = a.length; if (k < 1 || k > n) throw new IllegalArgumentException("Illegal number of positions."); int[] indexes = new int[n]; int total = (int) Math.pow(n, k); while (total-- > 0) { for (int i = 0; i < n - (n - k); i++) System.out.print(a[indexes[i]]); System.out.println(); if (decider.test(indexes)) break; for (int i = 0; i < n; i++) { if (indexes[i] >= n - 1) { indexes[i] = 0; } else { indexes[i]++; break; } } } } }
rp = [1,2,3].repeated_permutation(2) p rp.to_a p rp.take_while{|(a, b)| a + b < 5}
Convert the following code from Java to Ruby, ensuring the logic remains intact.
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); } }
puts "Enter a number of seconds:" seconds = gets.chomp.to_i puts "Enter a MP3 file to be played" mp3filepath = File.dirname(__FILE__) + "/" + gets.chomp + ".mp3" sleep(seconds) pid = fork{ exec 'mpg123','-q', mp3filepath }
Produce a language-to-language conversion: from Java to Ruby, same semantics.
import java.math.BigInteger; import java.util.*; class LeftTruncatablePrime { private static List<BigInteger> getNextLeftTruncatablePrimes(BigInteger n, int radix, int millerRabinCertainty) { List<BigInteger> probablePrimes = new ArrayList<BigInteger>(); String baseString = n.equals(BigInteger.ZERO) ? "" : n.toString(radix); for (int i = 1; i < radix; i++) { BigInteger p = new BigInteger(Integer.toString(i, radix) + baseString, radix); if (p.isProbablePrime(millerRabinCertainty)) probablePrimes.add(p); } return probablePrimes; } public static BigInteger getLargestLeftTruncatablePrime(int radix, int millerRabinCertainty) { List<BigInteger> lastList = null; List<BigInteger> list = getNextLeftTruncatablePrimes(BigInteger.ZERO, radix, millerRabinCertainty); while (!list.isEmpty()) { lastList = list; list = new ArrayList<BigInteger>(); for (BigInteger n : lastList) list.addAll(getNextLeftTruncatablePrimes(n, radix, millerRabinCertainty)); } if (lastList == null) return null; Collections.sort(lastList); return lastList.get(lastList.size() - 1); } public static void main(String[] args) { if (args.length != 2) { System.err.println("There must be exactly two command line arguments."); return; } int maxRadix; try { maxRadix = Integer.parseInt(args[0]); if (maxRadix < 3) throw new NumberFormatException(); } catch (NumberFormatException e) { System.err.println("Radix must be an integer greater than 2."); return; } int millerRabinCertainty; try { millerRabinCertainty = Integer.parseInt(args[1]); } catch (NumberFormatException e) { System.err.println("Miiller-Rabin Certainty must be an integer."); return; } for (int radix = 3; radix <= maxRadix; radix++) { BigInteger largest = getLargestLeftTruncatablePrime(radix, millerRabinCertainty); System.out.print("n=" + radix + ": "); if (largest == null) System.out.println("No left-truncatable prime"); else System.out.println(largest + " (in base " + radix + "): " + largest.toString(radix)); } } }
require 'prime' BASE = 3 MAX = 500 stems = Prime.each(BASE-1).to_a (1..MAX-1).each {|i| print " t = [] b = BASE ** i stems.each {|z| (1..BASE-1).each {|n| c = n*b+z t.push(c) if c.prime? }} break if t.empty? stems = t } puts "The largest left truncatable prime
Rewrite the snippet below in Ruby so it works the same as the original Java code.
import java.util.*; public class Game24Player { final String[] patterns = {"nnonnoo", "nnonono", "nnnoono", "nnnonoo", "nnnnooo"}; final String ops = "+-*/^"; String solution; List<Integer> digits; public static void main(String[] args) { new Game24Player().play(); } void play() { digits = getSolvableDigits(); Scanner in = new Scanner(System.in); while (true) { System.out.print("Make 24 using these digits: "); System.out.println(digits); System.out.println("(Enter 'q' to quit, 's' for a solution)"); System.out.print("> "); String line = in.nextLine(); if (line.equalsIgnoreCase("q")) { System.out.println("\nThanks for playing"); return; } if (line.equalsIgnoreCase("s")) { System.out.println(solution); digits = getSolvableDigits(); continue; } char[] entry = line.replaceAll("[^*+-/)(\\d]", "").toCharArray(); try { validate(entry); if (evaluate(infixToPostfix(entry))) { System.out.println("\nCorrect! Want to try another? "); digits = getSolvableDigits(); } else { System.out.println("\nNot correct."); } } catch (Exception e) { System.out.printf("%n%s Try again.%n", e.getMessage()); } } } void validate(char[] input) throws Exception { int total1 = 0, parens = 0, opsCount = 0; for (char c : input) { if (Character.isDigit(c)) total1 += 1 << (c - '0') * 4; else if (c == '(') parens++; else if (c == ')') parens--; else if (ops.indexOf(c) != -1) opsCount++; if (parens < 0) throw new Exception("Parentheses mismatch."); } if (parens != 0) throw new Exception("Parentheses mismatch."); if (opsCount != 3) throw new Exception("Wrong number of operators."); int total2 = 0; for (int d : digits) total2 += 1 << d * 4; if (total1 != total2) throw new Exception("Not the same digits."); } boolean evaluate(char[] line) throws Exception { Stack<Float> s = new Stack<>(); try { for (char c : line) { if ('0' <= c && c <= '9') s.push((float) c - '0'); else s.push(applyOperator(s.pop(), s.pop(), c)); } } catch (EmptyStackException e) { throw new Exception("Invalid entry."); } return (Math.abs(24 - s.peek()) < 0.001F); } float applyOperator(float a, float b, char c) { switch (c) { case '+': return a + b; case '-': return b - a; case '*': return a * b; case '/': return b / a; default: return Float.NaN; } } List<Integer> randomDigits() { Random r = new Random(); List<Integer> result = new ArrayList<>(4); for (int i = 0; i < 4; i++) result.add(r.nextInt(9) + 1); return result; } List<Integer> getSolvableDigits() { List<Integer> result; do { result = randomDigits(); } while (!isSolvable(result)); return result; } boolean isSolvable(List<Integer> digits) { Set<List<Integer>> dPerms = new HashSet<>(4 * 3 * 2); permute(digits, dPerms, 0); int total = 4 * 4 * 4; List<List<Integer>> oPerms = new ArrayList<>(total); permuteOperators(oPerms, 4, total); StringBuilder sb = new StringBuilder(4 + 3); for (String pattern : patterns) { char[] patternChars = pattern.toCharArray(); for (List<Integer> dig : dPerms) { for (List<Integer> opr : oPerms) { int i = 0, j = 0; for (char c : patternChars) { if (c == 'n') sb.append(dig.get(i++)); else sb.append(ops.charAt(opr.get(j++))); } String candidate = sb.toString(); try { if (evaluate(candidate.toCharArray())) { solution = postfixToInfix(candidate); return true; } } catch (Exception ignored) { } sb.setLength(0); } } } return false; } String postfixToInfix(String postfix) { class Expression { String op, ex; int prec = 3; Expression(String e) { ex = e; } Expression(String e1, String e2, String o) { ex = String.format("%s %s %s", e1, o, e2); op = o; prec = ops.indexOf(o) / 2; } } Stack<Expression> expr = new Stack<>(); for (char c : postfix.toCharArray()) { int idx = ops.indexOf(c); if (idx != -1) { Expression r = expr.pop(); Expression l = expr.pop(); int opPrec = idx / 2; if (l.prec < opPrec) l.ex = '(' + l.ex + ')'; if (r.prec <= opPrec) r.ex = '(' + r.ex + ')'; expr.push(new Expression(l.ex, r.ex, "" + c)); } else { expr.push(new Expression("" + c)); } } return expr.peek().ex; } char[] infixToPostfix(char[] infix) throws Exception { StringBuilder sb = new StringBuilder(); Stack<Integer> s = new Stack<>(); try { for (char c : infix) { int idx = ops.indexOf(c); if (idx != -1) { if (s.isEmpty()) s.push(idx); else { while (!s.isEmpty()) { int prec2 = s.peek() / 2; int prec1 = idx / 2; if (prec2 >= prec1) sb.append(ops.charAt(s.pop())); else break; } s.push(idx); } } else if (c == '(') { s.push(-2); } else if (c == ')') { while (s.peek() != -2) sb.append(ops.charAt(s.pop())); s.pop(); } else { sb.append(c); } } while (!s.isEmpty()) sb.append(ops.charAt(s.pop())); } catch (EmptyStackException e) { throw new Exception("Invalid entry."); } return sb.toString().toCharArray(); } void permute(List<Integer> lst, Set<List<Integer>> res, int k) { for (int i = k; i < lst.size(); i++) { Collections.swap(lst, i, k); permute(lst, res, k + 1); Collections.swap(lst, k, i); } if (k == lst.size()) res.add(new ArrayList<>(lst)); } void permuteOperators(List<List<Integer>> res, int n, int total) { for (int i = 0, npow = n * n; i < total; i++) res.add(Arrays.asList((i / npow), (i % npow) / n, i % n)); } }
class TwentyFourGame EXPRESSIONS = [ '((%dr %s %dr) %s %dr) %s %dr', '(%dr %s (%dr %s %dr)) %s %dr', '(%dr %s %dr) %s (%dr %s %dr)', '%dr %s ((%dr %s %dr) %s %dr)', '%dr %s (%dr %s (%dr %s %dr))', ] OPERATORS = [:+, :-, :*, :/].repeated_permutation(3).to_a def self.solve(digits) solutions = [] perms = digits.permutation.to_a.uniq perms.product(OPERATORS, EXPRESSIONS) do |(a,b,c,d), (op1,op2,op3), expr| text = expr % [a, op1, b, op2, c, op3, d] value = eval(text) rescue next solutions << text.delete("r") if value == 24 end solutions end end digits = ARGV.map do |arg| begin Integer(arg) rescue ArgumentError raise "error: not an integer: ' end end digits.size == 4 or raise "error: need 4 digits, only have solutions = TwentyFourGame.solve(digits) if solutions.empty? puts "no solutions" else puts "found puts solutions.sort end
Can you help me rewrite this code in Ruby instead of Java, keeping it the same logically?
import java.util.*; public class Game24Player { final String[] patterns = {"nnonnoo", "nnonono", "nnnoono", "nnnonoo", "nnnnooo"}; final String ops = "+-*/^"; String solution; List<Integer> digits; public static void main(String[] args) { new Game24Player().play(); } void play() { digits = getSolvableDigits(); Scanner in = new Scanner(System.in); while (true) { System.out.print("Make 24 using these digits: "); System.out.println(digits); System.out.println("(Enter 'q' to quit, 's' for a solution)"); System.out.print("> "); String line = in.nextLine(); if (line.equalsIgnoreCase("q")) { System.out.println("\nThanks for playing"); return; } if (line.equalsIgnoreCase("s")) { System.out.println(solution); digits = getSolvableDigits(); continue; } char[] entry = line.replaceAll("[^*+-/)(\\d]", "").toCharArray(); try { validate(entry); if (evaluate(infixToPostfix(entry))) { System.out.println("\nCorrect! Want to try another? "); digits = getSolvableDigits(); } else { System.out.println("\nNot correct."); } } catch (Exception e) { System.out.printf("%n%s Try again.%n", e.getMessage()); } } } void validate(char[] input) throws Exception { int total1 = 0, parens = 0, opsCount = 0; for (char c : input) { if (Character.isDigit(c)) total1 += 1 << (c - '0') * 4; else if (c == '(') parens++; else if (c == ')') parens--; else if (ops.indexOf(c) != -1) opsCount++; if (parens < 0) throw new Exception("Parentheses mismatch."); } if (parens != 0) throw new Exception("Parentheses mismatch."); if (opsCount != 3) throw new Exception("Wrong number of operators."); int total2 = 0; for (int d : digits) total2 += 1 << d * 4; if (total1 != total2) throw new Exception("Not the same digits."); } boolean evaluate(char[] line) throws Exception { Stack<Float> s = new Stack<>(); try { for (char c : line) { if ('0' <= c && c <= '9') s.push((float) c - '0'); else s.push(applyOperator(s.pop(), s.pop(), c)); } } catch (EmptyStackException e) { throw new Exception("Invalid entry."); } return (Math.abs(24 - s.peek()) < 0.001F); } float applyOperator(float a, float b, char c) { switch (c) { case '+': return a + b; case '-': return b - a; case '*': return a * b; case '/': return b / a; default: return Float.NaN; } } List<Integer> randomDigits() { Random r = new Random(); List<Integer> result = new ArrayList<>(4); for (int i = 0; i < 4; i++) result.add(r.nextInt(9) + 1); return result; } List<Integer> getSolvableDigits() { List<Integer> result; do { result = randomDigits(); } while (!isSolvable(result)); return result; } boolean isSolvable(List<Integer> digits) { Set<List<Integer>> dPerms = new HashSet<>(4 * 3 * 2); permute(digits, dPerms, 0); int total = 4 * 4 * 4; List<List<Integer>> oPerms = new ArrayList<>(total); permuteOperators(oPerms, 4, total); StringBuilder sb = new StringBuilder(4 + 3); for (String pattern : patterns) { char[] patternChars = pattern.toCharArray(); for (List<Integer> dig : dPerms) { for (List<Integer> opr : oPerms) { int i = 0, j = 0; for (char c : patternChars) { if (c == 'n') sb.append(dig.get(i++)); else sb.append(ops.charAt(opr.get(j++))); } String candidate = sb.toString(); try { if (evaluate(candidate.toCharArray())) { solution = postfixToInfix(candidate); return true; } } catch (Exception ignored) { } sb.setLength(0); } } } return false; } String postfixToInfix(String postfix) { class Expression { String op, ex; int prec = 3; Expression(String e) { ex = e; } Expression(String e1, String e2, String o) { ex = String.format("%s %s %s", e1, o, e2); op = o; prec = ops.indexOf(o) / 2; } } Stack<Expression> expr = new Stack<>(); for (char c : postfix.toCharArray()) { int idx = ops.indexOf(c); if (idx != -1) { Expression r = expr.pop(); Expression l = expr.pop(); int opPrec = idx / 2; if (l.prec < opPrec) l.ex = '(' + l.ex + ')'; if (r.prec <= opPrec) r.ex = '(' + r.ex + ')'; expr.push(new Expression(l.ex, r.ex, "" + c)); } else { expr.push(new Expression("" + c)); } } return expr.peek().ex; } char[] infixToPostfix(char[] infix) throws Exception { StringBuilder sb = new StringBuilder(); Stack<Integer> s = new Stack<>(); try { for (char c : infix) { int idx = ops.indexOf(c); if (idx != -1) { if (s.isEmpty()) s.push(idx); else { while (!s.isEmpty()) { int prec2 = s.peek() / 2; int prec1 = idx / 2; if (prec2 >= prec1) sb.append(ops.charAt(s.pop())); else break; } s.push(idx); } } else if (c == '(') { s.push(-2); } else if (c == ')') { while (s.peek() != -2) sb.append(ops.charAt(s.pop())); s.pop(); } else { sb.append(c); } } while (!s.isEmpty()) sb.append(ops.charAt(s.pop())); } catch (EmptyStackException e) { throw new Exception("Invalid entry."); } return sb.toString().toCharArray(); } void permute(List<Integer> lst, Set<List<Integer>> res, int k) { for (int i = k; i < lst.size(); i++) { Collections.swap(lst, i, k); permute(lst, res, k + 1); Collections.swap(lst, k, i); } if (k == lst.size()) res.add(new ArrayList<>(lst)); } void permuteOperators(List<List<Integer>> res, int n, int total) { for (int i = 0, npow = n * n; i < total; i++) res.add(Arrays.asList((i / npow), (i % npow) / n, i % n)); } }
class TwentyFourGame EXPRESSIONS = [ '((%dr %s %dr) %s %dr) %s %dr', '(%dr %s (%dr %s %dr)) %s %dr', '(%dr %s %dr) %s (%dr %s %dr)', '%dr %s ((%dr %s %dr) %s %dr)', '%dr %s (%dr %s (%dr %s %dr))', ] OPERATORS = [:+, :-, :*, :/].repeated_permutation(3).to_a def self.solve(digits) solutions = [] perms = digits.permutation.to_a.uniq perms.product(OPERATORS, EXPRESSIONS) do |(a,b,c,d), (op1,op2,op3), expr| text = expr % [a, op1, b, op2, c, op3, d] value = eval(text) rescue next solutions << text.delete("r") if value == 24 end solutions end end digits = ARGV.map do |arg| begin Integer(arg) rescue ArgumentError raise "error: not an integer: ' end end digits.size == 4 or raise "error: need 4 digits, only have solutions = TwentyFourGame.solve(digits) if solutions.empty? puts "no solutions" else puts "found puts solutions.sort end
Generate an equivalent Ruby version of this Java code.
import java.awt.image.*; import java.io.File; import java.io.IOException; import javax.imageio.*; public class HoughTransform { public static ArrayData houghTransform(ArrayData inputData, int thetaAxisSize, int rAxisSize, int minContrast) { int width = inputData.width; int height = inputData.height; int maxRadius = (int)Math.ceil(Math.hypot(width, height)); int halfRAxisSize = rAxisSize >>> 1; ArrayData outputData = new ArrayData(thetaAxisSize, rAxisSize); double[] sinTable = new double[thetaAxisSize]; double[] cosTable = new double[thetaAxisSize]; for (int theta = thetaAxisSize - 1; theta >= 0; theta--) { double thetaRadians = theta * Math.PI / thetaAxisSize; sinTable[theta] = Math.sin(thetaRadians); cosTable[theta] = Math.cos(thetaRadians); } for (int y = height - 1; y >= 0; y--) { for (int x = width - 1; x >= 0; x--) { if (inputData.contrast(x, y, minContrast)) { for (int theta = thetaAxisSize - 1; theta >= 0; theta--) { double r = cosTable[theta] * x + sinTable[theta] * y; int rScaled = (int)Math.round(r * halfRAxisSize / maxRadius) + halfRAxisSize; outputData.accumulate(theta, rScaled, 1); } } } } return outputData; } public static class ArrayData { public final int[] dataArray; public final int width; public final int height; public ArrayData(int width, int height) { this(new int[width * height], width, height); } public ArrayData(int[] dataArray, int width, int height) { this.dataArray = dataArray; this.width = width; this.height = height; } public int get(int x, int y) { return dataArray[y * width + x]; } public void set(int x, int y, int value) { dataArray[y * width + x] = value; } public void accumulate(int x, int y, int delta) { set(x, y, get(x, y) + delta); } public boolean contrast(int x, int y, int minContrast) { int centerValue = get(x, y); for (int i = 8; i >= 0; i--) { if (i == 4) continue; int newx = x + (i % 3) - 1; int newy = y + (i / 3) - 1; if ((newx < 0) || (newx >= width) || (newy < 0) || (newy >= height)) continue; if (Math.abs(get(newx, newy) - centerValue) >= minContrast) return true; } return false; } public int getMax() { int max = dataArray[0]; for (int i = width * height - 1; i > 0; i--) if (dataArray[i] > max) max = dataArray[i]; return max; } } public static ArrayData getArrayDataFromImage(String filename) throws IOException { BufferedImage inputImage = ImageIO.read(new File(filename)); int width = inputImage.getWidth(); int height = inputImage.getHeight(); int[] rgbData = inputImage.getRGB(0, 0, width, height, null, 0, width); ArrayData arrayData = new ArrayData(width, height); for (int y = 0; y < height; y++) { for (int x = 0; x < width; x++) { int rgbValue = rgbData[y * width + x]; rgbValue = (int)(((rgbValue & 0xFF0000) >>> 16) * 0.30 + ((rgbValue & 0xFF00) >>> 8) * 0.59 + (rgbValue & 0xFF) * 0.11); arrayData.set(x, height - 1 - y, rgbValue); } } return arrayData; } public static void writeOutputImage(String filename, ArrayData arrayData) throws IOException { int max = arrayData.getMax(); BufferedImage outputImage = new BufferedImage(arrayData.width, arrayData.height, BufferedImage.TYPE_INT_ARGB); for (int y = 0; y < arrayData.height; y++) { for (int x = 0; x < arrayData.width; x++) { int n = Math.min((int)Math.round(arrayData.get(x, y) * 255.0 / max), 255); outputImage.setRGB(x, arrayData.height - 1 - y, (n << 16) | (n << 8) | 0x90 | -0x01000000); } } ImageIO.write(outputImage, "PNG", new File(filename)); return; } public static void main(String[] args) throws IOException { ArrayData inputData = getArrayDataFromImage(args[0]); int minContrast = (args.length >= 4) ? 64 : Integer.parseInt(args[4]); ArrayData outputData = houghTransform(inputData, Integer.parseInt(args[2]), Integer.parseInt(args[3]), minContrast); writeOutputImage(args[1], outputData); return; } }
require 'mathn' require 'rubygems' require 'gd2' include GD2 def hough_transform(img) mx, my = img.w*0.5, img.h*0.5 max_d = Math.sqrt(mx**2 + my**2) min_d = max_d * -1 hough = Hash.new(0) (0..img.w).each do |x| puts " (0..img.h).each do |y| if img.pixel2color(img.get_pixel(x,y)).g > 32 (0...180).each do |a| rad = a * (Math::PI / 180.0) d = (x-mx) * Math.cos(rad) + (y-my) * Math.sin(rad) hough[" end end end end heat = GD2::Image.import 'heatmap.png' out = GD2::Image::TrueColor.new(180,max_d*2) max = hough.values.max p max hough.each_pair do |k,v| a,d = k.split('_').map(&:to_i) c = (v / max) * 255 c = heat.get_pixel(c,0) out.set_pixel(a, max_d + d, c) end out end
Generate an equivalent Ruby version of this Java code.
import java.math.BigInteger; import java.util.List; import java.util.Map; import java.util.function.BiFunction; import java.util.function.Function; public class TonelliShanks { private static final BigInteger ZERO = BigInteger.ZERO; private static final BigInteger ONE = BigInteger.ONE; private static final BigInteger TEN = BigInteger.TEN; private static final BigInteger TWO = BigInteger.valueOf(2); private static final BigInteger FOUR = BigInteger.valueOf(4); private static class Solution { private BigInteger root1; private BigInteger root2; private boolean exists; Solution(BigInteger root1, BigInteger root2, boolean exists) { this.root1 = root1; this.root2 = root2; this.exists = exists; } } private static Solution ts(Long n, Long p) { return ts(BigInteger.valueOf(n), BigInteger.valueOf(p)); } private static Solution ts(BigInteger n, BigInteger p) { BiFunction<BigInteger, BigInteger, BigInteger> powModP = (BigInteger a, BigInteger e) -> a.modPow(e, p); Function<BigInteger, BigInteger> ls = (BigInteger a) -> powModP.apply(a, p.subtract(ONE).divide(TWO)); if (!ls.apply(n).equals(ONE)) return new Solution(ZERO, ZERO, false); BigInteger q = p.subtract(ONE); BigInteger ss = ZERO; while (q.and(ONE).equals(ZERO)) { ss = ss.add(ONE); q = q.shiftRight(1); } if (ss.equals(ONE)) { BigInteger r1 = powModP.apply(n, p.add(ONE).divide(FOUR)); return new Solution(r1, p.subtract(r1), true); } BigInteger z = TWO; while (!ls.apply(z).equals(p.subtract(ONE))) z = z.add(ONE); BigInteger c = powModP.apply(z, q); BigInteger r = powModP.apply(n, q.add(ONE).divide(TWO)); BigInteger t = powModP.apply(n, q); BigInteger m = ss; while (true) { if (t.equals(ONE)) return new Solution(r, p.subtract(r), true); BigInteger i = ZERO; BigInteger zz = t; while (!zz.equals(BigInteger.ONE) && i.compareTo(m.subtract(ONE)) < 0) { zz = zz.multiply(zz).mod(p); i = i.add(ONE); } BigInteger b = c; BigInteger e = m.subtract(i).subtract(ONE); while (e.compareTo(ZERO) > 0) { b = b.multiply(b).mod(p); e = e.subtract(ONE); } r = r.multiply(b).mod(p); c = b.multiply(b).mod(p); t = t.multiply(c).mod(p); m = i; } } public static void main(String[] args) { List<Map.Entry<Long, Long>> pairs = List.of( Map.entry(10L, 13L), Map.entry(56L, 101L), Map.entry(1030L, 10009L), Map.entry(1032L, 10009L), Map.entry(44402L, 100049L), Map.entry(665820697L, 1000000009L), Map.entry(881398088036L, 1000000000039L) ); for (Map.Entry<Long, Long> pair : pairs) { Solution sol = ts(pair.getKey(), pair.getValue()); System.out.printf("n = %s\n", pair.getKey()); System.out.printf("p = %s\n", pair.getValue()); if (sol.exists) { System.out.printf("root1 = %s\n", sol.root1); System.out.printf("root2 = %s\n", sol.root2); } else { System.out.println("No solution exists"); } System.out.println(); } BigInteger bn = new BigInteger("41660815127637347468140745042827704103445750172002"); BigInteger bp = TEN.pow(50).add(BigInteger.valueOf(577)); Solution sol = ts(bn, bp); System.out.printf("n = %s\n", bn); System.out.printf("p = %s\n", bp); if (sol.exists) { System.out.printf("root1 = %s\n", sol.root1); System.out.printf("root2 = %s\n", sol.root2); } else { System.out.println("No solution exists"); } } }
func tonelli(n, p) { legendre(n, p) == 1 || die "not a square (mod p)" var q = p-1 var s = valuation(q, 2) s == 1 ? return(powmod(n, (p + 1) >> 2, p)) : (q >>= s) var c = powmod(2 ..^ p -> first {|z| legendre(z, p) == -1}, q, p) var r = powmod(n, (q + 1) >> 1, p) var t = powmod(n, q, p) var m = s var t2 = 0 while (!p.divides(t - 1)) { t2 = ((t * t) % p) var b for i in (1 ..^ m) { if (p.divides(t2 - 1)) { b = powmod(c, 1 << (m - i - 1), p) m = i break } t2 = ((t2 * t2) % p) } r = ((r * b) % p) c = ((b * b) % p) t = ((t * c) % p) } return r } var tests = [ [10, 13], [56, 101], [1030, 10009], [44402, 100049], [665820697, 1000000009], [881398088036, 1000000000039], [41660815127637347468140745042827704103445750172002, 10**50 + 577], ] for n,p in tests { var r = tonelli(n, p) assert((r*r - n) % p == 0) say "Roots of }
Convert this Java block to Ruby, preserving its control flow and logic.
import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.LinkedHashSet; import java.util.List; import java.util.Map; import java.util.Set; import java.util.Stack; public class TruthTable { public static void main( final String... args ) { System.out.println( new TruthTable( args ) ); } private interface Operator { boolean evaluate( Stack<Boolean> s ); } private static final Map<String,Operator> operators = new HashMap<String,Operator>() {{ put( "&", stack -> Boolean.logicalAnd( stack.pop(), stack.pop() ) ); put( "|", stack -> Boolean.logicalOr( stack.pop(), stack.pop() ) ); put( "!", stack -> ! stack.pop() ); put( "^", stack -> ! stack.pop().equals ( stack.pop() ) ); }}; private final List<String> variables; private final String[] symbols; public TruthTable( final String... symbols ) { final Set<String> variables = new LinkedHashSet<>(); for ( final String symbol : symbols ) { if ( ! operators.containsKey( symbol ) ) { variables.add( symbol ); } } this.variables = new ArrayList<>( variables ); this.symbols = symbols; } @Override public String toString () { final StringBuilder result = new StringBuilder(); for ( final String variable : variables ) { result.append( variable ).append( ' ' ); } result.append( ' ' ); for ( final String symbol : symbols ) { result.append( symbol ).append ( ' ' ); } result.append( '\n' ); for ( final List<Boolean> values : enumerate( variables.size () ) ) { final Iterator<String> i = variables.iterator(); for ( final Boolean value : values ) { result.append( String.format( "%-" + i.next().length() + "c ", value ? 'T' : 'F' ) ); } result.append( ' ' ) .append( evaluate( values ) ? 'T' : 'F' ) .append( '\n' ); } return result.toString (); } private static List<List<Boolean>> enumerate( final int size ) { if ( 1 == size ) return new ArrayList<List<Boolean>>() {{ add( new ArrayList<Boolean>() {{ add(false); }} ); add( new ArrayList<Boolean>() {{ add(true); }} ); }}; return new ArrayList<List<Boolean>>() {{ for ( final List<Boolean> head : enumerate( size - 1 ) ) { add( new ArrayList<Boolean>( head ) {{ add(false); }} ); add( new ArrayList<Boolean>( head ) {{ add(true); }} ); } }}; } private boolean evaluate( final List<Boolean> enumeration ) { final Iterator<Boolean> i = enumeration.iterator(); final Map<String,Boolean> values = new HashMap<>(); final Stack<Boolean> stack = new Stack<>(); variables.forEach ( v -> values.put( v, i.next() ) ); for ( final String symbol : symbols ) { final Operator op = operators.get ( symbol ); stack.push( null == op ? values.get ( symbol ) : op.evaluate ( stack ) ); } return stack.pop(); } }
loop do print "\ninput a boolean expression (e.g. 'a & b'): " expr = gets.strip.downcase break if expr.empty? vars = expr.scan(/\p{Alpha}+/) if vars.empty? puts "no variables detected in your boolean expression" next end vars.each {|v| print " puts "| prefix = [] suffix = [] vars.each do |v| prefix << "[false, true].each do | suffix << "end" end body = vars.inject("puts ") {|str, v| str + " body += '"| " + eval(expr).to_s' eval (prefix + [body] + suffix).join("\n") end
Convert this Java block to Ruby, preserving its control flow and logic.
import java.util.Objects; import java.util.function.Predicate; public class RealNumberSet { public enum RangeType { CLOSED, BOTH_OPEN, LEFT_OPEN, RIGHT_OPEN, } public static class RealSet { private Double low; private Double high; private Predicate<Double> predicate; private double interval = 0.00001; public RealSet(Double low, Double high, Predicate<Double> predicate) { this.low = low; this.high = high; this.predicate = predicate; } public RealSet(Double start, Double end, RangeType rangeType) { this(start, end, d -> { switch (rangeType) { case CLOSED: return start <= d && d <= end; case BOTH_OPEN: return start < d && d < end; case LEFT_OPEN: return start < d && d <= end; case RIGHT_OPEN: return start <= d && d < end; default: throw new IllegalStateException("Unhandled range type encountered."); } }); } public boolean contains(Double d) { return predicate.test(d); } public RealSet union(RealSet other) { double low2 = Math.min(low, other.low); double high2 = Math.max(high, other.high); return new RealSet(low2, high2, d -> predicate.or(other.predicate).test(d)); } public RealSet intersect(RealSet other) { double low2 = Math.min(low, other.low); double high2 = Math.max(high, other.high); return new RealSet(low2, high2, d -> predicate.and(other.predicate).test(d)); } public RealSet subtract(RealSet other) { return new RealSet(low, high, d -> predicate.and(other.predicate.negate()).test(d)); } public double length() { if (low.isInfinite() || high.isInfinite()) return -1.0; if (high <= low) return 0.0; Double p = low; int count = 0; do { if (predicate.test(p)) count++; p += interval; } while (p < high); return count * interval; } public boolean isEmpty() { if (Objects.equals(high, low)) { return predicate.negate().test(low); } return length() == 0.0; } } public static void main(String[] args) { RealSet a = new RealSet(0.0, 1.0, RangeType.LEFT_OPEN); RealSet b = new RealSet(0.0, 2.0, RangeType.RIGHT_OPEN); RealSet c = new RealSet(1.0, 2.0, RangeType.LEFT_OPEN); RealSet d = new RealSet(0.0, 3.0, RangeType.RIGHT_OPEN); RealSet e = new RealSet(0.0, 1.0, RangeType.BOTH_OPEN); RealSet f = new RealSet(0.0, 1.0, RangeType.CLOSED); RealSet g = new RealSet(0.0, 0.0, RangeType.CLOSED); for (int i = 0; i <= 2; i++) { Double dd = (double) i; System.out.printf("(0, 1] ∪ [0, 2) contains %d is %s\n", i, a.union(b).contains(dd)); System.out.printf("[0, 2) ∩ (1, 2] contains %d is %s\n", i, b.intersect(c).contains(dd)); System.out.printf("[0, 3) − (0, 1) contains %d is %s\n", i, d.subtract(e).contains(dd)); System.out.printf("[0, 3) − [0, 1] contains %d is %s\n", i, d.subtract(f).contains(dd)); System.out.println(); } System.out.printf("[0, 0] is empty is %s\n", g.isEmpty()); System.out.println(); RealSet aa = new RealSet( 0.0, 10.0, x -> (0.0 < x && x < 10.0) && Math.abs(Math.sin(Math.PI * x * x)) > 0.5 ); RealSet bb = new RealSet( 0.0, 10.0, x -> (0.0 < x && x < 10.0) && Math.abs(Math.sin(Math.PI * x)) > 0.5 ); RealSet cc = aa.subtract(bb); System.out.printf("Approx length of A - B is %f\n", cc.length()); } }
class Rset Set = Struct.new(:lo, :hi, :inc_lo, :inc_hi) do def include?(x) (inc_lo ? lo<=x : lo<x) and (inc_hi ? x<=hi : x<hi) end def length hi - lo end def to_s " end end def initialize(lo=nil, hi=nil, inc_lo=false, inc_hi=false) if lo.nil? and hi.nil? @sets = [] else raise TypeError unless lo.is_a?(Numeric) and hi.is_a?(Numeric) raise ArgumentError unless valid?(lo, hi, inc_lo, inc_hi) @sets = [Set[lo, hi, !!inc_lo, !!inc_hi]] end end def self.[](lo, hi, inc_hi=true) self.new(lo, hi, true, inc_hi) end def self.parse(str) raise ArgumentError unless str =~ /(\[|\()(.+),(.+)(\]|\))/ b0, lo, hi, b1 = $~.captures lo = Rational(lo) lo = lo.numerator if lo.denominator == 1 hi = Rational(hi) hi = hi.numerator if hi.denominator == 1 self.new(lo, hi, b0=='[', b1==']') end def initialize_copy(obj) super @sets = @sets.map(&:dup) end def include?(x) @sets.any?{|set| set.include?(x)} end def empty? @sets.empty? end def union(other) sets = (@sets+other.sets).map(&:dup).sort_by{|set| [set.lo, set.hi]} work = [] pre = sets.shift sets.each do |post| if valid?(pre.hi, post.lo, !pre.inc_hi, !post.inc_lo) work << pre pre = post else pre.inc_lo |= post.inc_lo if pre.lo == post.lo if pre.hi < post.hi pre.hi = post.hi pre.inc_hi = post.inc_hi elsif pre.hi == post.hi pre.inc_hi |= post.inc_hi end end end work << pre if pre new_Rset(work) end alias | union def intersection(other) sets = @sets.map(&:dup) work = [] other.sets.each do |oset| sets.each do |set| if set.hi < oset.lo or oset.hi < set.lo elsif oset.lo < set.lo and set.hi < oset.hi work << set else lo = [set.lo, oset.lo].max if set.lo == oset.lo inc_lo = set.inc_lo && oset.inc_lo else inc_lo = (set.lo < oset.lo) ? oset.inc_lo : set.inc_lo end hi = [set.hi, oset.hi].min if set.hi == oset.hi inc_hi = set.inc_hi && oset.inc_hi else inc_hi = (set.hi < oset.hi) ? set.inc_hi : oset.inc_hi end work << Set[lo, hi, inc_lo, inc_hi] if valid?(lo, hi, inc_lo, inc_hi) end end end new_Rset(work) end alias & intersection def difference(other) sets = @sets.map(&:dup) other.sets.each do |oset| work = [] sets.each do |set| if set.hi < oset.lo or oset.hi < set.lo work << set elsif oset.lo < set.lo and set.hi < oset.hi else if set.lo < oset.lo inc_hi = (set.hi==oset.lo and !set.inc_hi) ? false : !oset.inc_lo work << Set[set.lo, oset.lo, set.inc_lo, inc_hi] elsif valid?(set.lo, oset.lo, set.inc_lo, !oset.inc_lo) work << Set[set.lo, set.lo, true, true] end if oset.hi < set.hi inc_lo = (oset.hi==set.lo and !set.inc_lo) ? false : !oset.inc_hi work << Set[oset.hi, set.hi, inc_lo, set.inc_hi] elsif valid?(oset.hi, set.hi, !oset.inc_hi, set.inc_hi) work << Set[set.hi, set.hi, true, true] end end end sets = work end new_Rset(sets) end alias - difference def ^(other) (self - other) | (other - self) end def ==(other) self.class == other.class and @sets == other.sets end def length @sets.inject(0){|len, set| len + set.length} end def to_s " end alias inspect to_s protected attr_accessor :sets private def new_Rset(sets) rset = self.class.new rset.sets = sets rset end def valid?(lo, hi, inc_lo, inc_hi) lo < hi or (lo==hi and inc_lo and inc_hi) end end def Rset(lo, hi, inc_hi=false) Rset.new(lo, hi, false, inc_hi) end
Rewrite this program in Ruby while keeping its functionality equivalent to the Java version.
import java.util.Objects; import java.util.function.Predicate; public class RealNumberSet { public enum RangeType { CLOSED, BOTH_OPEN, LEFT_OPEN, RIGHT_OPEN, } public static class RealSet { private Double low; private Double high; private Predicate<Double> predicate; private double interval = 0.00001; public RealSet(Double low, Double high, Predicate<Double> predicate) { this.low = low; this.high = high; this.predicate = predicate; } public RealSet(Double start, Double end, RangeType rangeType) { this(start, end, d -> { switch (rangeType) { case CLOSED: return start <= d && d <= end; case BOTH_OPEN: return start < d && d < end; case LEFT_OPEN: return start < d && d <= end; case RIGHT_OPEN: return start <= d && d < end; default: throw new IllegalStateException("Unhandled range type encountered."); } }); } public boolean contains(Double d) { return predicate.test(d); } public RealSet union(RealSet other) { double low2 = Math.min(low, other.low); double high2 = Math.max(high, other.high); return new RealSet(low2, high2, d -> predicate.or(other.predicate).test(d)); } public RealSet intersect(RealSet other) { double low2 = Math.min(low, other.low); double high2 = Math.max(high, other.high); return new RealSet(low2, high2, d -> predicate.and(other.predicate).test(d)); } public RealSet subtract(RealSet other) { return new RealSet(low, high, d -> predicate.and(other.predicate.negate()).test(d)); } public double length() { if (low.isInfinite() || high.isInfinite()) return -1.0; if (high <= low) return 0.0; Double p = low; int count = 0; do { if (predicate.test(p)) count++; p += interval; } while (p < high); return count * interval; } public boolean isEmpty() { if (Objects.equals(high, low)) { return predicate.negate().test(low); } return length() == 0.0; } } public static void main(String[] args) { RealSet a = new RealSet(0.0, 1.0, RangeType.LEFT_OPEN); RealSet b = new RealSet(0.0, 2.0, RangeType.RIGHT_OPEN); RealSet c = new RealSet(1.0, 2.0, RangeType.LEFT_OPEN); RealSet d = new RealSet(0.0, 3.0, RangeType.RIGHT_OPEN); RealSet e = new RealSet(0.0, 1.0, RangeType.BOTH_OPEN); RealSet f = new RealSet(0.0, 1.0, RangeType.CLOSED); RealSet g = new RealSet(0.0, 0.0, RangeType.CLOSED); for (int i = 0; i <= 2; i++) { Double dd = (double) i; System.out.printf("(0, 1] ∪ [0, 2) contains %d is %s\n", i, a.union(b).contains(dd)); System.out.printf("[0, 2) ∩ (1, 2] contains %d is %s\n", i, b.intersect(c).contains(dd)); System.out.printf("[0, 3) − (0, 1) contains %d is %s\n", i, d.subtract(e).contains(dd)); System.out.printf("[0, 3) − [0, 1] contains %d is %s\n", i, d.subtract(f).contains(dd)); System.out.println(); } System.out.printf("[0, 0] is empty is %s\n", g.isEmpty()); System.out.println(); RealSet aa = new RealSet( 0.0, 10.0, x -> (0.0 < x && x < 10.0) && Math.abs(Math.sin(Math.PI * x * x)) > 0.5 ); RealSet bb = new RealSet( 0.0, 10.0, x -> (0.0 < x && x < 10.0) && Math.abs(Math.sin(Math.PI * x)) > 0.5 ); RealSet cc = aa.subtract(bb); System.out.printf("Approx length of A - B is %f\n", cc.length()); } }
class Rset Set = Struct.new(:lo, :hi, :inc_lo, :inc_hi) do def include?(x) (inc_lo ? lo<=x : lo<x) and (inc_hi ? x<=hi : x<hi) end def length hi - lo end def to_s " end end def initialize(lo=nil, hi=nil, inc_lo=false, inc_hi=false) if lo.nil? and hi.nil? @sets = [] else raise TypeError unless lo.is_a?(Numeric) and hi.is_a?(Numeric) raise ArgumentError unless valid?(lo, hi, inc_lo, inc_hi) @sets = [Set[lo, hi, !!inc_lo, !!inc_hi]] end end def self.[](lo, hi, inc_hi=true) self.new(lo, hi, true, inc_hi) end def self.parse(str) raise ArgumentError unless str =~ /(\[|\()(.+),(.+)(\]|\))/ b0, lo, hi, b1 = $~.captures lo = Rational(lo) lo = lo.numerator if lo.denominator == 1 hi = Rational(hi) hi = hi.numerator if hi.denominator == 1 self.new(lo, hi, b0=='[', b1==']') end def initialize_copy(obj) super @sets = @sets.map(&:dup) end def include?(x) @sets.any?{|set| set.include?(x)} end def empty? @sets.empty? end def union(other) sets = (@sets+other.sets).map(&:dup).sort_by{|set| [set.lo, set.hi]} work = [] pre = sets.shift sets.each do |post| if valid?(pre.hi, post.lo, !pre.inc_hi, !post.inc_lo) work << pre pre = post else pre.inc_lo |= post.inc_lo if pre.lo == post.lo if pre.hi < post.hi pre.hi = post.hi pre.inc_hi = post.inc_hi elsif pre.hi == post.hi pre.inc_hi |= post.inc_hi end end end work << pre if pre new_Rset(work) end alias | union def intersection(other) sets = @sets.map(&:dup) work = [] other.sets.each do |oset| sets.each do |set| if set.hi < oset.lo or oset.hi < set.lo elsif oset.lo < set.lo and set.hi < oset.hi work << set else lo = [set.lo, oset.lo].max if set.lo == oset.lo inc_lo = set.inc_lo && oset.inc_lo else inc_lo = (set.lo < oset.lo) ? oset.inc_lo : set.inc_lo end hi = [set.hi, oset.hi].min if set.hi == oset.hi inc_hi = set.inc_hi && oset.inc_hi else inc_hi = (set.hi < oset.hi) ? set.inc_hi : oset.inc_hi end work << Set[lo, hi, inc_lo, inc_hi] if valid?(lo, hi, inc_lo, inc_hi) end end end new_Rset(work) end alias & intersection def difference(other) sets = @sets.map(&:dup) other.sets.each do |oset| work = [] sets.each do |set| if set.hi < oset.lo or oset.hi < set.lo work << set elsif oset.lo < set.lo and set.hi < oset.hi else if set.lo < oset.lo inc_hi = (set.hi==oset.lo and !set.inc_hi) ? false : !oset.inc_lo work << Set[set.lo, oset.lo, set.inc_lo, inc_hi] elsif valid?(set.lo, oset.lo, set.inc_lo, !oset.inc_lo) work << Set[set.lo, set.lo, true, true] end if oset.hi < set.hi inc_lo = (oset.hi==set.lo and !set.inc_lo) ? false : !oset.inc_hi work << Set[oset.hi, set.hi, inc_lo, set.inc_hi] elsif valid?(oset.hi, set.hi, !oset.inc_hi, set.inc_hi) work << Set[set.hi, set.hi, true, true] end end end sets = work end new_Rset(sets) end alias - difference def ^(other) (self - other) | (other - self) end def ==(other) self.class == other.class and @sets == other.sets end def length @sets.inject(0){|len, set| len + set.length} end def to_s " end alias inspect to_s protected attr_accessor :sets private def new_Rset(sets) rset = self.class.new rset.sets = sets rset end def valid?(lo, hi, inc_lo, inc_hi) lo < hi or (lo==hi and inc_lo and inc_hi) end end def Rset(lo, hi, inc_hi=false) Rset.new(lo, hi, false, inc_hi) end
Rewrite the snippet below in Ruby so it works the same as the original Java code.
import java.util.*; import java.util.stream.*; public class StateNamePuzzle { static String[] states = {"Alabama", "Alaska", "Arizona", "Arkansas", "California", "Colorado", "Connecticut", "Delaware", "Florida", "Georgia", "hawaii", "Hawaii", "Idaho", "Illinois", "Indiana", "Iowa", "Kansas", "Kentucky", "Louisiana", "Maine", "Maryland", "Massachusetts", "Michigan", "Minnesota", "Mississippi", "Missouri", "Montana", "Nebraska", "Nevada", "New Hampshire", "New Jersey", "New Mexico", "New York", "North Carolina ", "North Dakota", "Ohio", "Oklahoma", "Oregon", "Pennsylvania", "Rhode Island", "South Carolina", "South Dakota", "Tennessee", "Texas", "Utah", "Vermont", "Virginia", "Washington", "West Virginia", "Wisconsin", "Wyoming", "New Kory", "Wen Kory", "York New", "Kory New", "New Kory",}; public static void main(String[] args) { solve(Arrays.asList(states)); } static void solve(List<String> input) { Map<String, String> orig = input.stream().collect(Collectors.toMap( s -> s.replaceAll("\\s", "").toLowerCase(), s -> s, (s, a) -> s)); input = new ArrayList<>(orig.keySet()); Map<String, List<String[]>> map = new HashMap<>(); for (int i = 0; i < input.size() - 1; i++) { String pair0 = input.get(i); for (int j = i + 1; j < input.size(); j++) { String[] pair = {pair0, input.get(j)}; String s = pair0 + pair[1]; String key = Arrays.toString(s.chars().sorted().toArray()); List<String[]> val = map.getOrDefault(key, new ArrayList<>()); val.add(pair); map.put(key, val); } } map.forEach((key, list) -> { for (int i = 0; i < list.size() - 1; i++) { String[] a = list.get(i); for (int j = i + 1; j < list.size(); j++) { String[] b = list.get(j); if (Stream.of(a[0], a[1], b[0], b[1]).distinct().count() < 4) continue; System.out.printf("%s + %s = %s + %s %n", orig.get(a[0]), orig.get(a[1]), orig.get(b[0]), orig.get(b[1])); } } }); } }
require 'set' Primes = [ 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, 101] States = [ "Alabama", "Alaska", "Arizona", "Arkansas", "California", "Colorado", "Connecticut", "Delaware", "Florida", "Georgia", "Hawaii", "Idaho", "Illinois", "Indiana", "Iowa", "Kansas", "Kentucky", "Louisiana", "Maine", "Maryland", "Massachusetts", "Michigan", "Minnesota", "Mississippi", "Missouri", "Montana", "Nebraska", "Nevada", "New Hampshire", "New Jersey", "New Mexico", "New York", "North Carolina", "North Dakota", "Ohio", "Oklahoma", "Oregon", "Pennsylvania", "Rhode Island", "South Carolina", "South Dakota", "Tennessee", "Texas", "Utah", "Vermont", "Virginia", "Washington", "West Virginia", "Wisconsin", "Wyoming" ] def print_answer(states) goedel = lambda {|str| str.chars.map {|c| Primes[c.ord - 65]}.reduce(:*)} pairs = Hash.new {|h,k| h[k] = Array.new} map = states.uniq.map {|state| [state, goedel[state.upcase.delete("^A-Z")]]} map.combination(2) {|(s1,g1), (s2,g2)| pairs[g1 * g2] << [s1, s2]} result = [] pairs.values.select {|val| val.length > 1}.each do |list_of_pairs| list_of_pairs.combination(2) do |pair1, pair2| if Set[*pair1, *pair2].length == 4 result << [pair1, pair2] end end end result.each_with_index do |(pair1, pair2), i| puts "%d\t%s\t%s" % [i+1, pair1.join(', '), pair2.join(', ')] end end puts "real states only" print_answer(States) puts "" puts "with fictional states" print_answer(States + ["New Kory", "Wen Kory", "York New", "Kory New", "New Kory"])
Convert this Java block to Ruby, preserving its control flow and logic.
import java.math.BigInteger; public class SuperDNumbers { public static void main(String[] args) { for ( int i = 2 ; i <= 9 ; i++ ) { superD(i, 10); } } private static final void superD(int d, int max) { long start = System.currentTimeMillis(); String test = ""; for ( int i = 0 ; i < d ; i++ ) { test += (""+d); } int n = 0; int i = 0; System.out.printf("First %d super-%d numbers: %n", max, d); while ( n < max ) { i++; BigInteger val = BigInteger.valueOf(d).multiply(BigInteger.valueOf(i).pow(d)); if ( val.toString().contains(test) ) { n++; System.out.printf("%d ", i); } } long end = System.currentTimeMillis(); System.out.printf("%nRun time %d ms%n%n", end-start); } }
(2..8).each do |d| rep = d.to_s * d print " puts (2..).lazy.select{|n| (d * n**d).to_s.include?(rep) }.first(10).join(", ") end
Produce a language-to-language conversion: from Java to Ruby, same semantics.
import java.io.IOException; import java.nio.charset.StandardCharsets; import java.nio.file.Path; import java.nio.file.Paths; import java.util.Arrays; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Scanner; import java.util.Vector; public class RTextonyms { private static final Map<Character, Character> mapping; private int total, elements, textonyms, max_found; private String filename, mappingResult; private Vector<String> max_strings; private Map<String, Vector<String>> values; static { mapping = new HashMap<Character, Character>(); mapping.put('A', '2'); mapping.put('B', '2'); mapping.put('C', '2'); mapping.put('D', '3'); mapping.put('E', '3'); mapping.put('F', '3'); mapping.put('G', '4'); mapping.put('H', '4'); mapping.put('I', '4'); mapping.put('J', '5'); mapping.put('K', '5'); mapping.put('L', '5'); mapping.put('M', '6'); mapping.put('N', '6'); mapping.put('O', '6'); mapping.put('P', '7'); mapping.put('Q', '7'); mapping.put('R', '7'); mapping.put('S', '7'); mapping.put('T', '8'); mapping.put('U', '8'); mapping.put('V', '8'); mapping.put('W', '9'); mapping.put('X', '9'); mapping.put('Y', '9'); mapping.put('Z', '9'); } public RTextonyms(String filename) { this.filename = filename; this.total = this.elements = this.textonyms = this.max_found = 0; this.values = new HashMap<String, Vector<String>>(); this.max_strings = new Vector<String>(); return; } public void add(String line) { String mapping = ""; total++; if (!get_mapping(line)) { return; } mapping = mappingResult; if (values.get(mapping) == null) { values.put(mapping, new Vector<String>()); } int num_strings; num_strings = values.get(mapping).size(); textonyms += num_strings == 1 ? 1 : 0; elements++; if (num_strings > max_found) { max_strings.clear(); max_strings.add(mapping); max_found = num_strings; } else if (num_strings == max_found) { max_strings.add(mapping); } values.get(mapping).add(line); return; } public void results() { System.out.printf("Read %,d words from %s%n%n", total, filename); System.out.printf("There are %,d words in %s which can be represented by the digit key mapping.%n", elements, filename); System.out.printf("They require %,d digit combinations to represent them.%n", values.size()); System.out.printf("%,d digit combinations represent Textonyms.%n", textonyms); System.out.printf("The numbers mapping to the most words map to %,d words each:%n", max_found + 1); for (String key : max_strings) { System.out.printf("%16s maps to: %s%n", key, values.get(key).toString()); } System.out.println(); return; } public void match(String key) { Vector<String> match; match = values.get(key); if (match == null) { System.out.printf("Key %s not found%n", key); } else { System.out.printf("Key %s matches: %s%n", key, match.toString()); } return; } private boolean get_mapping(String line) { mappingResult = line; StringBuilder mappingBuilder = new StringBuilder(); for (char cc : line.toCharArray()) { if (Character.isAlphabetic(cc)) { mappingBuilder.append(mapping.get(Character.toUpperCase(cc))); } else if (Character.isDigit(cc)) { mappingBuilder.append(cc); } else { return false; } } mappingResult = mappingBuilder.toString(); return true; } public static void main(String[] args) { String filename; if (args.length > 0) { filename = args[0]; } else { filename = "./unixdict.txt"; } RTextonyms tc; tc = new RTextonyms(filename); Path fp = Paths.get(filename); try (Scanner fs = new Scanner(fp, StandardCharsets.UTF_8.name())) { while (fs.hasNextLine()) { tc.add(fs.nextLine()); } } catch (IOException ex) { ex.printStackTrace(); } List<String> numbers = Arrays.asList( "001", "228", "27484247", "7244967473642", "." ); tc.results(); for (String number : numbers) { if (number.equals(".")) { System.out.println(); } else { tc.match(number); } } return; } }
CHARS = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" NUMS = "22233344455566677778889999" * 2 dict = "unixdict.txt" textonyms = File.open(dict){|f| f.map(&:chomp).group_by {|word| word.tr(CHARS, NUMS) } } puts "There are They require puts "\n25287876746242:
Rewrite this program in Ruby while keeping its functionality equivalent to the Java version.
package lvijay; import java.util.concurrent.atomic.AtomicInteger; import java.util.function.Function; public class Church { public static interface ChurchNum extends Function<ChurchNum, ChurchNum> { } public static ChurchNum zero() { return f -> x -> x; } public static ChurchNum next(ChurchNum n) { return f -> x -> f.apply(n.apply(f).apply(x)); } public static ChurchNum plus(ChurchNum a) { return b -> f -> x -> b.apply(f).apply(a.apply(f).apply(x)); } public static ChurchNum pow(ChurchNum m) { return n -> m.apply(n); } public static ChurchNum mult(ChurchNum a) { return b -> f -> x -> b.apply(a.apply(f)).apply(x); } public static ChurchNum toChurchNum(int n) { if (n <= 0) { return zero(); } return next(toChurchNum(n - 1)); } public static int toInt(ChurchNum c) { AtomicInteger counter = new AtomicInteger(0); ChurchNum funCounter = f -> { counter.incrementAndGet(); return f; }; plus(zero()).apply(c).apply(funCounter).apply(x -> x); return counter.get(); } public static void main(String[] args) { ChurchNum zero = zero(); ChurchNum three = next(next(next(zero))); ChurchNum four = next(next(next(next(zero)))); System.out.println("3+4=" + toInt(plus(three).apply(four))); System.out.println("4+3=" + toInt(plus(four).apply(three))); System.out.println("3*4=" + toInt(mult(three).apply(four))); System.out.println("4*3=" + toInt(mult(four).apply(three))); System.out.println("3^4=" + toInt(pow(four).apply(three))); System.out.println("4^3=" + toInt(pow(three).apply(four))); System.out.println(" 8=" + toInt(toChurchNum(8))); } }
def zero(f) return lambda {|x| x} end Zero = lambda { |f| zero(f) } def succ(n) return lambda { |f| lambda { |x| f.(n.(f).(x)) } } end Three = succ(succ(succ(Zero))) def add(n, m) return lambda { |f| lambda { |x| m.(f).(n.(f).(x)) } } end def mult(n, m) return lambda { |f| lambda { |x| m.(n.(f)).(x) } } end def power(b, e) return e.(b) end def int_from_couch(f) countup = lambda { |i| i+1 } f.(countup).(0) end def couch_from_int(x) countdown = lambda { |i| case i when 0 then Zero else succ(countdown.(i-1)) end } countdown.(x) end Four = couch_from_int(4) puts [ add(Three, Four), mult(Three, Four), power(Three, Four), power(Four, Three) ].map {|f| int_from_couch(f) }
Can you help me rewrite this code in Ruby instead of Java, keeping it the same logically?
package lvijay; import java.util.concurrent.atomic.AtomicInteger; import java.util.function.Function; public class Church { public static interface ChurchNum extends Function<ChurchNum, ChurchNum> { } public static ChurchNum zero() { return f -> x -> x; } public static ChurchNum next(ChurchNum n) { return f -> x -> f.apply(n.apply(f).apply(x)); } public static ChurchNum plus(ChurchNum a) { return b -> f -> x -> b.apply(f).apply(a.apply(f).apply(x)); } public static ChurchNum pow(ChurchNum m) { return n -> m.apply(n); } public static ChurchNum mult(ChurchNum a) { return b -> f -> x -> b.apply(a.apply(f)).apply(x); } public static ChurchNum toChurchNum(int n) { if (n <= 0) { return zero(); } return next(toChurchNum(n - 1)); } public static int toInt(ChurchNum c) { AtomicInteger counter = new AtomicInteger(0); ChurchNum funCounter = f -> { counter.incrementAndGet(); return f; }; plus(zero()).apply(c).apply(funCounter).apply(x -> x); return counter.get(); } public static void main(String[] args) { ChurchNum zero = zero(); ChurchNum three = next(next(next(zero))); ChurchNum four = next(next(next(next(zero)))); System.out.println("3+4=" + toInt(plus(three).apply(four))); System.out.println("4+3=" + toInt(plus(four).apply(three))); System.out.println("3*4=" + toInt(mult(three).apply(four))); System.out.println("4*3=" + toInt(mult(four).apply(three))); System.out.println("3^4=" + toInt(pow(four).apply(three))); System.out.println("4^3=" + toInt(pow(three).apply(four))); System.out.println(" 8=" + toInt(toChurchNum(8))); } }
def zero(f) return lambda {|x| x} end Zero = lambda { |f| zero(f) } def succ(n) return lambda { |f| lambda { |x| f.(n.(f).(x)) } } end Three = succ(succ(succ(Zero))) def add(n, m) return lambda { |f| lambda { |x| m.(f).(n.(f).(x)) } } end def mult(n, m) return lambda { |f| lambda { |x| m.(n.(f)).(x) } } end def power(b, e) return e.(b) end def int_from_couch(f) countup = lambda { |i| i+1 } f.(countup).(0) end def couch_from_int(x) countdown = lambda { |i| case i when 0 then Zero else succ(countdown.(i-1)) end } countdown.(x) end Four = couch_from_int(4) puts [ add(Three, Four), mult(Three, Four), power(Three, Four), power(Four, Three) ].map {|f| int_from_couch(f) }
Can you help me rewrite this code in Ruby instead of Java, keeping it the same logically?
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); } } }
class Super CLASSNAME = 'super' def initialize(name) @name = name def self.superOwn 'super owned' end end def to_s "Super( end def doSup 'did super stuff' end def self.superClassStuff 'did super class stuff' end protected def protSup "Super's protected" end private def privSup "Super's private" end end module Other def otherStuff 'did other stuff' end end class Sub < Super CLASSNAME = 'sub' attr_reader :dynamic include Other def initialize(name, *args) super(name) @rest = args; @dynamic = {} def self.subOwn 'sub owned' end end def methods(regular=true) super + @dynamic.keys end def method_missing(name, *args, &block) return super unless @dynamic.member?(name) method = @dynamic[name] if method.arity > 0 if method.parameters[0][1] == :self args.unshift(self) end if method.lambda? args += args + [nil] * [method.arity - args.length, 0].max if method.parameters[-1][0] != :rest args = args[0,method.arity] end end method.call(*args) else method.call end end def public_methods(all=true) super + @dynamic.keys end def respond_to?(symbol, include_all=false) @dynamic.member?(symbol) || super end def to_s "Sub( end def doSub 'did sub stuff' end def self.subClassStuff 'did sub class stuff' end protected def protSub "Sub's protected" end private def privSub "Sub's private" end end sup = Super.new('sup') sub = Sub.new('sub', 0, 'I', 'two') sub.dynamic[:incr] = proc {|i| i+1} p sub.public_methods(false) p sub.methods - Object.methods p sub.public_methods - Object.public_methods p sub.methods - sup.methods p sub.methods(false) p sub.singleton_methods
Translate this program into Ruby but keep the logic exactly as in Java.
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); } }
class Example def foo 42 end def bar(arg1, arg2, &block) block.call arg1, arg2 end end symbol = :foo Example.new.send symbol Example.new.send( :bar, 1, 2 ) { |x,y| x+y } args = [1, 2] Example.new.send( "bar", *args ) { |x,y| x+y }
Write the same algorithm in Ruby as shown in this Java implementation.
import java.text.MessageFormat; import java.text.ParseException; public class CanonicalizeCIDR { public static void main(String[] args) { for (String test : TESTS) { try { CIDR cidr = new CIDR(test); System.out.printf("%-18s -> %s\n", test, cidr.toString()); } catch (Exception ex) { System.err.printf("Error parsing '%s': %s\n", test, ex.getLocalizedMessage()); } } } private static class CIDR { private CIDR(int address, int maskLength) { this.address = address; this.maskLength = maskLength; } private CIDR(String str) throws Exception { Object[] args = new MessageFormat(FORMAT).parse(str); int address = 0; for (int i = 0; i < 4; ++i) { int a = ((Number)args[i]).intValue(); if (a < 0 || a > 255) throw new Exception("Invalid IP address"); address <<= 8; address += a; } int maskLength = ((Number)args[4]).intValue(); if (maskLength < 1 || maskLength > 32) throw new Exception("Invalid mask length"); int mask = ~((1 << (32 - maskLength)) - 1); this.address = address & mask; this.maskLength = maskLength; } public String toString() { int address = this.address; int d = address & 0xFF; address >>= 8; int c = address & 0xFF; address >>= 8; int b = address & 0xFF; address >>= 8; int a = address & 0xFF; Object[] args = { a, b, c, d, maskLength }; return new MessageFormat(FORMAT).format(args); } private int address; private int maskLength; private static final String FORMAT = "{0,number,integer}.{1,number,integer}.{2,number,integer}.{3,number,integer}/{4,number,integer}"; }; private static final String[] TESTS = { "87.70.141.1/22", "36.18.154.103/12", "62.62.197.11/29", "67.137.119.181/4", "161.214.74.21/24", "184.232.176.184/18" }; }
if ARGV.length == 0 then ARGV = $stdin.readlines.map(&:chomp) end ARGV.each do |cidr| dotted, size_str = cidr.split('/') size = size_str.to_i binary = dotted.split('.').map { |o| "%08b" % o }.join binary[size .. -1] = '0' * (32 - size) canon = binary.chars.each_slice(8).map { |a| a.join.to_i(2) }.join('.') puts " end
Convert this Java block to Ruby, preserving its control flow and logic.
import java.text.MessageFormat; import java.text.ParseException; public class CanonicalizeCIDR { public static void main(String[] args) { for (String test : TESTS) { try { CIDR cidr = new CIDR(test); System.out.printf("%-18s -> %s\n", test, cidr.toString()); } catch (Exception ex) { System.err.printf("Error parsing '%s': %s\n", test, ex.getLocalizedMessage()); } } } private static class CIDR { private CIDR(int address, int maskLength) { this.address = address; this.maskLength = maskLength; } private CIDR(String str) throws Exception { Object[] args = new MessageFormat(FORMAT).parse(str); int address = 0; for (int i = 0; i < 4; ++i) { int a = ((Number)args[i]).intValue(); if (a < 0 || a > 255) throw new Exception("Invalid IP address"); address <<= 8; address += a; } int maskLength = ((Number)args[4]).intValue(); if (maskLength < 1 || maskLength > 32) throw new Exception("Invalid mask length"); int mask = ~((1 << (32 - maskLength)) - 1); this.address = address & mask; this.maskLength = maskLength; } public String toString() { int address = this.address; int d = address & 0xFF; address >>= 8; int c = address & 0xFF; address >>= 8; int b = address & 0xFF; address >>= 8; int a = address & 0xFF; Object[] args = { a, b, c, d, maskLength }; return new MessageFormat(FORMAT).format(args); } private int address; private int maskLength; private static final String FORMAT = "{0,number,integer}.{1,number,integer}.{2,number,integer}.{3,number,integer}/{4,number,integer}"; }; private static final String[] TESTS = { "87.70.141.1/22", "36.18.154.103/12", "62.62.197.11/29", "67.137.119.181/4", "161.214.74.21/24", "184.232.176.184/18" }; }
if ARGV.length == 0 then ARGV = $stdin.readlines.map(&:chomp) end ARGV.each do |cidr| dotted, size_str = cidr.split('/') size = size_str.to_i binary = dotted.split('.').map { |o| "%08b" % o }.join binary[size .. -1] = '0' * (32 - size) canon = binary.chars.each_slice(8).map { |a| a.join.to_i(2) }.join('.') puts " end
Produce a language-to-language conversion: from Java to Ruby, same semantics.
import java.math.BigInteger; public class PrimorialPrimes { final static int sieveLimit = 1550_000; static boolean[] notPrime = sieve(sieveLimit); public static void main(String[] args) { int count = 0; for (int i = 1; i < 1000_000 && count < 20; i++) { BigInteger b = primorial(i); if (b.add(BigInteger.ONE).isProbablePrime(1) || b.subtract(BigInteger.ONE).isProbablePrime(1)) { System.out.printf("%d ", i); count++; } } } static BigInteger primorial(int n) { if (n == 0) return BigInteger.ONE; BigInteger result = BigInteger.ONE; for (int i = 0; i < sieveLimit && n > 0; i++) { if (notPrime[i]) continue; result = result.multiply(BigInteger.valueOf(i)); n--; } return result; } public static boolean[] sieve(int limit) { boolean[] composite = new boolean[limit]; composite[0] = composite[1] = true; int max = (int) Math.sqrt(limit); for (int n = 2; n <= max; n++) { if (!composite[n]) { for (int k = n * n; k < limit; k += n) { composite[k] = true; } } } return composite; } }
require 'prime' require 'openssl' i, urutan, primorial_number = 1, 1, OpenSSL::BN.new(1) start = Time.now prime_array = Prime.first (500) until urutan > 20 primorial_number *= prime_array[i-1] if (primorial_number - 1).prime_fasttest? || (primorial_number + 1).prime_fasttest? puts " urutan += 1 end i += 1 end
Keep all operations the same but rewrite the snippet in Ruby.
import java.math.BigInteger; public class CombinationsAndPermutations { public static void main(String[] args) { System.out.println(Double.MAX_VALUE); System.out.println("A sample of permutations from 1 to 12 with exact Integer arithmetic:"); for ( int n = 1 ; n <= 12 ; n++ ) { int k = n / 2; System.out.printf("%d P %d = %s%n", n, k, permutation(n, k)); } System.out.println(); System.out.println("A sample of combinations from 10 to 60 with exact Integer arithmetic:"); for ( int n = 10 ; n <= 60 ; n += 5 ) { int k = n / 2; System.out.printf("%d C %d = %s%n", n, k, combination(n, k)); } System.out.println(); System.out.println("A sample of permutations from 5 to 15000 displayed in floating point arithmetic:"); System.out.printf("%d P %d = %s%n", 5, 2, display(permutation(5, 2), 50)); for ( int n = 1000 ; n <= 15000 ; n += 1000 ) { int k = n / 2; System.out.printf("%d P %d = %s%n", n, k, display(permutation(n, k), 50)); } System.out.println(); System.out.println("A sample of combinations from 100 to 1000 displayed in floating point arithmetic:"); for ( int n = 100 ; n <= 1000 ; n += 100 ) { int k = n / 2; System.out.printf("%d C %d = %s%n", n, k, display(combination(n, k), 50)); } } private static String display(BigInteger val, int precision) { String s = val.toString(); precision = Math.min(precision, s.length()); StringBuilder sb = new StringBuilder(); sb.append(s.substring(0, 1)); sb.append("."); sb.append(s.substring(1, precision)); sb.append(" * 10^"); sb.append(s.length()-1); return sb.toString(); } public static BigInteger combination(int n, int k) { if ( n-k < k ) { k = n-k; } BigInteger result = permutation(n, k); while ( k > 0 ) { result = result.divide(BigInteger.valueOf(k)); k--; } return result; } public static BigInteger permutation(int n, int k) { BigInteger result = BigInteger.ONE; for ( int i = n ; i >= n-k+1 ; i-- ) { result = result.multiply(BigInteger.valueOf(i)); } return result; } }
require "big" include Math struct Int def permutation(k) (self-k+1..self).product(1.to_big_i) end def combination(k) self.permutation(k) // (1..k).product(1.to_big_i) end def big_permutation(k) exp(lgamma_plus(self) - lgamma_plus(self-k)) end def big_combination(k) exp( lgamma_plus(self) - lgamma_plus(self - k) - lgamma_plus(k)) end private def lgamma_plus(n) lgamma(n+1) end end p 12.permutation(9) p 12.big_permutation(9) p 60.combination(53) p 145.big_permutation(133) p 900.big_combination(450) p 1000.big_combination(969) p 15000.big_permutation(73) p 15000.big_permutation(74) p 15000.permutation(74)
Maintain the same structure and functionality when rewriting this code in Ruby.
import java.math.BigDecimal; import java.math.MathContext; import java.util.Objects; public class Calculate_Pi { private static final MathContext con1024 = new MathContext(1024); private static final BigDecimal bigTwo = new BigDecimal(2); private static final BigDecimal bigFour = new BigDecimal(4); private static BigDecimal bigSqrt(BigDecimal bd, MathContext con) { BigDecimal x0 = BigDecimal.ZERO; BigDecimal x1 = BigDecimal.valueOf(Math.sqrt(bd.doubleValue())); while (!Objects.equals(x0, x1)) { x0 = x1; x1 = bd.divide(x0, con).add(x0).divide(bigTwo, con); } return x1; } public static void main(String[] args) { BigDecimal a = BigDecimal.ONE; BigDecimal g = a.divide(bigSqrt(bigTwo, con1024), con1024); BigDecimal t; BigDecimal sum = BigDecimal.ZERO; BigDecimal pow = bigTwo; while (!Objects.equals(a, g)) { t = a.add(g).divide(bigTwo, con1024); g = bigSqrt(a.multiply(g), con1024); a = t; pow = pow.multiply(bigTwo); sum = sum.add(a.multiply(a).subtract(g.multiply(g)).multiply(pow)); } BigDecimal pi = bigFour.multiply(a.multiply(a)).divide(BigDecimal.ONE.subtract(sum), con1024); System.out.println(pi); } }
require 'flt' Flt::BinNum.Context.precision = 8192 a = n = 1 g = 1 / Flt::BinNum(2).sqrt z = 0.25 (0..17).each{ x = [(a + g) * 0.5, (a * g).sqrt] var = x[0] - a z -= var * var * n n += n a = x[0] g = x[1] } puts a * a / z
Generate a Ruby translation of this Java snippet without changing its computational steps.
import java.math.BigDecimal; import java.math.MathContext; import java.util.Objects; public class Calculate_Pi { private static final MathContext con1024 = new MathContext(1024); private static final BigDecimal bigTwo = new BigDecimal(2); private static final BigDecimal bigFour = new BigDecimal(4); private static BigDecimal bigSqrt(BigDecimal bd, MathContext con) { BigDecimal x0 = BigDecimal.ZERO; BigDecimal x1 = BigDecimal.valueOf(Math.sqrt(bd.doubleValue())); while (!Objects.equals(x0, x1)) { x0 = x1; x1 = bd.divide(x0, con).add(x0).divide(bigTwo, con); } return x1; } public static void main(String[] args) { BigDecimal a = BigDecimal.ONE; BigDecimal g = a.divide(bigSqrt(bigTwo, con1024), con1024); BigDecimal t; BigDecimal sum = BigDecimal.ZERO; BigDecimal pow = bigTwo; while (!Objects.equals(a, g)) { t = a.add(g).divide(bigTwo, con1024); g = bigSqrt(a.multiply(g), con1024); a = t; pow = pow.multiply(bigTwo); sum = sum.add(a.multiply(a).subtract(g.multiply(g)).multiply(pow)); } BigDecimal pi = bigFour.multiply(a.multiply(a)).divide(BigDecimal.ONE.subtract(sum), con1024); System.out.println(pi); } }
require 'flt' Flt::BinNum.Context.precision = 8192 a = n = 1 g = 1 / Flt::BinNum(2).sqrt z = 0.25 (0..17).each{ x = [(a + g) * 0.5, (a * g).sqrt] var = x[0] - a z -= var * var * n n += n a = x[0] g = x[1] } puts a * a / z
Can you help me rewrite this code in Ruby instead of Java, keeping it the same logically?
import java.util.LinkedList; import java.util.List; public class LongPrimes { private static void sieve(int limit, List<Integer> primes) { boolean[] c = new boolean[limit]; for (int i = 0; i < limit; i++) c[i] = false; int p = 3, n = 0; int p2 = p * p; while (p2 <= limit) { for (int i = p2; i <= limit; i += 2 * p) c[i] = true; do p += 2; while (c[p]); p2 = p * p; } for (int i = 3; i <= limit; i += 2) if (!c[i]) primes.add(i); } private static int findPeriod(int n) { int r = 1, period = 0; for (int i = 1; i < n; i++) r = (10 * r) % n; int rr = r; do { r = (10 * r) % n; ++period; } while (r != rr); return period; } public static void main(String[] args) { int[] numbers = new int[]{500, 1000, 2000, 4000, 8000, 16000, 32000, 64000}; int[] totals = new int[numbers.length]; List<Integer> primes = new LinkedList<Integer>(); List<Integer> longPrimes = new LinkedList<Integer>(); sieve(64000, primes); for (int prime : primes) if (findPeriod(prime) == prime - 1) longPrimes.add(prime); int count = 0, index = 0; for (int longPrime : longPrimes) { if (longPrime > numbers[index]) totals[index++] = count; ++count; } totals[numbers.length - 1] = count; System.out.println("The long primes up to " + numbers[0] + " are:"); System.out.println(longPrimes.subList(0, totals[0])); System.out.println(); System.out.println("The number of long primes up to:"); for (int i = 0; i <= 7; i++) System.out.printf(" %5d is %d\n", numbers[i], totals[i]); } }
require "big" def prime?(n) return n | 1 == 3 if n < 5 return false if n.gcd(6) != 1 pc = typeof(n).new(5) until pc*pc > n return false if n % pc == 0 || n % (pc + 2) == 0 pc += 6 end true end def long_prime?(p) return false unless prime? p (2...p).each do |d| return d == (p - 1) if (p - 1) % d == 0 && (10.to_big_i ** d) % p == 1 end false end start = Time.monotonic puts "Long primes ≤ 500:" (2..500).each { |pc| print " puts [500, 1000, 2000, 4000, 8000, 16000, 32000, 64000].each do |n| puts "Number of long primes ≤ end puts "\nTime:
Change the following Java code into Ruby without altering its purpose.
import java.math.BigInteger; public class PrimorialNumbers { final static int sieveLimit = 1300_000; static boolean[] notPrime = sieve(sieveLimit); public static void main(String[] args) { for (int i = 0; i < 10; i++) System.out.printf("primorial(%d): %d%n", i, primorial(i)); for (int i = 1; i < 6; i++) { int len = primorial((int) Math.pow(10, i)).toString().length(); System.out.printf("primorial(10^%d) has length %d%n", i, len); } } static BigInteger primorial(int n) { if (n == 0) return BigInteger.ONE; BigInteger result = BigInteger.ONE; for (int i = 0; i < sieveLimit && n > 0; i++) { if (notPrime[i]) continue; result = result.multiply(BigInteger.valueOf(i)); n--; } return result; } public static boolean[] sieve(int limit) { boolean[] composite = new boolean[limit]; composite[0] = composite[1] = true; int max = (int) Math.sqrt(limit); for (int n = 2; n <= max; n++) { if (!composite[n]) { for (int k = n * n; k < limit; k += n) { composite[k] = true; } } } return composite; } }
require 'prime' def primorial_number(n) pgen = Prime.each (1..n).inject(1){|p,_| p*pgen.next} end puts "First ten primorials: (1..5).each do |n| puts "primorial(10** end
Write the same code in Ruby as shown below in Java.
import java.math.BigDecimal; import java.math.BigInteger; import java.math.MathContext; import java.util.ArrayList; import java.util.Collections; import java.util.List; public class EgyptianFractions { private static BigInteger gcd(BigInteger a, BigInteger b) { if (b.equals(BigInteger.ZERO)) { return a; } return gcd(b, a.mod(b)); } private static class Frac implements Comparable<Frac> { private BigInteger num, denom; public Frac(BigInteger n, BigInteger d) { if (d.equals(BigInteger.ZERO)) { throw new IllegalArgumentException("Parameter d may not be zero."); } BigInteger nn = n; BigInteger dd = d; if (nn.equals(BigInteger.ZERO)) { dd = BigInteger.ONE; } else if (dd.compareTo(BigInteger.ZERO) < 0) { nn = nn.negate(); dd = dd.negate(); } BigInteger g = gcd(nn, dd).abs(); if (g.compareTo(BigInteger.ZERO) > 0) { nn = nn.divide(g); dd = dd.divide(g); } num = nn; denom = dd; } public Frac(int n, int d) { this(BigInteger.valueOf(n), BigInteger.valueOf(d)); } public Frac plus(Frac rhs) { return new Frac( num.multiply(rhs.denom).add(denom.multiply(rhs.num)), rhs.denom.multiply(denom) ); } public Frac unaryMinus() { return new Frac(num.negate(), denom); } public Frac minus(Frac rhs) { return plus(rhs.unaryMinus()); } @Override public int compareTo(Frac rhs) { BigDecimal diff = this.toBigDecimal().subtract(rhs.toBigDecimal()); if (diff.compareTo(BigDecimal.ZERO) < 0) { return -1; } if (BigDecimal.ZERO.compareTo(diff) < 0) { return 1; } return 0; } @Override public boolean equals(Object obj) { if (null == obj || !(obj instanceof Frac)) { return false; } Frac rhs = (Frac) obj; return compareTo(rhs) == 0; } @Override public String toString() { if (denom.equals(BigInteger.ONE)) { return num.toString(); } return String.format("%s/%s", num, denom); } public BigDecimal toBigDecimal() { BigDecimal bdn = new BigDecimal(num); BigDecimal bdd = new BigDecimal(denom); return bdn.divide(bdd, MathContext.DECIMAL128); } public List<Frac> toEgyptian() { if (num.equals(BigInteger.ZERO)) { return Collections.singletonList(this); } List<Frac> fracs = new ArrayList<>(); if (num.abs().compareTo(denom.abs()) >= 0) { Frac div = new Frac(num.divide(denom), BigInteger.ONE); Frac rem = this.minus(div); fracs.add(div); toEgyptian(rem.num, rem.denom, fracs); } else { toEgyptian(num, denom, fracs); } return fracs; } public void toEgyptian(BigInteger n, BigInteger d, List<Frac> fracs) { if (n.equals(BigInteger.ZERO)) { return; } BigDecimal n2 = new BigDecimal(n); BigDecimal d2 = new BigDecimal(d); BigDecimal[] divRem = d2.divideAndRemainder(n2, MathContext.UNLIMITED); BigInteger div = divRem[0].toBigInteger(); if (divRem[1].compareTo(BigDecimal.ZERO) > 0) { div = div.add(BigInteger.ONE); } fracs.add(new Frac(BigInteger.ONE, div)); BigInteger n3 = d.negate().mod(n); if (n3.compareTo(BigInteger.ZERO) < 0) { n3 = n3.add(n); } BigInteger d3 = d.multiply(div); Frac f = new Frac(n3, d3); if (f.num.equals(BigInteger.ONE)) { fracs.add(f); return; } toEgyptian(f.num, f.denom, fracs); } } public static void main(String[] args) { List<Frac> fracs = List.of( new Frac(43, 48), new Frac(5, 121), new Frac(2014, 59) ); for (Frac frac : fracs) { List<Frac> list = frac.toEgyptian(); Frac first = list.get(0); if (first.denom.equals(BigInteger.ONE)) { System.out.printf("%s -> [%s] + ", frac, first); } else { System.out.printf("%s -> %s", frac, first); } for (int i = 1; i < list.size(); ++i) { System.out.printf(" + %s", list.get(i)); } System.out.println(); } for (Integer r : List.of(98, 998)) { if (r == 98) { System.out.println("\nFor proper fractions with 1 or 2 digits:"); } else { System.out.println("\nFor proper fractions with 1, 2 or 3 digits:"); } int maxSize = 0; List<Frac> maxSizeFracs = new ArrayList<>(); BigInteger maxDen = BigInteger.ZERO; List<Frac> maxDenFracs = new ArrayList<>(); boolean[][] sieve = new boolean[r + 1][]; for (int i = 0; i < r + 1; ++i) { sieve[i] = new boolean[r + 2]; } for (int i = 1; i < r; ++i) { for (int j = i + 1; j < r + 1; ++j) { if (sieve[i][j]) continue; Frac f = new Frac(i, j); List<Frac> list = f.toEgyptian(); int listSize = list.size(); if (listSize > maxSize) { maxSize = listSize; maxSizeFracs.clear(); maxSizeFracs.add(f); } else if (listSize == maxSize) { maxSizeFracs.add(f); } BigInteger listDen = list.get(list.size() - 1).denom; if (listDen.compareTo(maxDen) > 0) { maxDen = listDen; maxDenFracs.clear(); maxDenFracs.add(f); } else if (listDen.equals(maxDen)) { maxDenFracs.add(f); } if (i < r / 2) { int k = 2; while (true) { if (j * k > r + 1) break; sieve[i * k][j * k] = true; k++; } } } } System.out.printf(" largest number of items = %s\n", maxSize); System.out.printf("fraction(s) with this number : %s\n", maxSizeFracs); String md = maxDen.toString(); System.out.printf(" largest denominator = %s digits, ", md.length()); System.out.printf("%s...%s\n", md.substring(0, 20), md.substring(md.length() - 20, md.length())); System.out.printf("fraction(s) with this denominator : %s\n", maxDenFracs); } } }
def ef(fr) ans = [] if fr >= 1 return [[fr.to_i], Rational(0, 1)] if fr.denominator == 1 intfr = fr.to_i ans, fr = [intfr], fr - intfr end x, y = fr.numerator, fr.denominator while x != 1 ans << Rational(1, (1/fr).ceil) fr = Rational(-y % x, y * (1/fr).ceil) x, y = fr.numerator, fr.denominator end ans << fr end for fr in [Rational(43, 48), Rational(5, 121), Rational(2014, 59)] puts '%s => %s' % [fr, ef(fr).join(' + ')] end lenmax = denommax = [0] for b in 2..99 for a in 1...b fr = Rational(a,b) e = ef(fr) elen, edenom = e.length, e[-1].denominator lenmax = [elen, fr] if elen > lenmax[0] denommax = [edenom, fr] if edenom > denommax[0] end end puts 'Term max is %s with %i terms' % [lenmax[1], lenmax[0]] dstr = denommax[0].to_s puts 'Denominator max is %s with %i digits' % [denommax[1], dstr.size], dstr
Produce a functionally identical Ruby code for the snippet given in Java.
import java.math.BigDecimal; import java.math.BigInteger; import java.math.MathContext; import java.util.ArrayList; import java.util.Collections; import java.util.List; public class EgyptianFractions { private static BigInteger gcd(BigInteger a, BigInteger b) { if (b.equals(BigInteger.ZERO)) { return a; } return gcd(b, a.mod(b)); } private static class Frac implements Comparable<Frac> { private BigInteger num, denom; public Frac(BigInteger n, BigInteger d) { if (d.equals(BigInteger.ZERO)) { throw new IllegalArgumentException("Parameter d may not be zero."); } BigInteger nn = n; BigInteger dd = d; if (nn.equals(BigInteger.ZERO)) { dd = BigInteger.ONE; } else if (dd.compareTo(BigInteger.ZERO) < 0) { nn = nn.negate(); dd = dd.negate(); } BigInteger g = gcd(nn, dd).abs(); if (g.compareTo(BigInteger.ZERO) > 0) { nn = nn.divide(g); dd = dd.divide(g); } num = nn; denom = dd; } public Frac(int n, int d) { this(BigInteger.valueOf(n), BigInteger.valueOf(d)); } public Frac plus(Frac rhs) { return new Frac( num.multiply(rhs.denom).add(denom.multiply(rhs.num)), rhs.denom.multiply(denom) ); } public Frac unaryMinus() { return new Frac(num.negate(), denom); } public Frac minus(Frac rhs) { return plus(rhs.unaryMinus()); } @Override public int compareTo(Frac rhs) { BigDecimal diff = this.toBigDecimal().subtract(rhs.toBigDecimal()); if (diff.compareTo(BigDecimal.ZERO) < 0) { return -1; } if (BigDecimal.ZERO.compareTo(diff) < 0) { return 1; } return 0; } @Override public boolean equals(Object obj) { if (null == obj || !(obj instanceof Frac)) { return false; } Frac rhs = (Frac) obj; return compareTo(rhs) == 0; } @Override public String toString() { if (denom.equals(BigInteger.ONE)) { return num.toString(); } return String.format("%s/%s", num, denom); } public BigDecimal toBigDecimal() { BigDecimal bdn = new BigDecimal(num); BigDecimal bdd = new BigDecimal(denom); return bdn.divide(bdd, MathContext.DECIMAL128); } public List<Frac> toEgyptian() { if (num.equals(BigInteger.ZERO)) { return Collections.singletonList(this); } List<Frac> fracs = new ArrayList<>(); if (num.abs().compareTo(denom.abs()) >= 0) { Frac div = new Frac(num.divide(denom), BigInteger.ONE); Frac rem = this.minus(div); fracs.add(div); toEgyptian(rem.num, rem.denom, fracs); } else { toEgyptian(num, denom, fracs); } return fracs; } public void toEgyptian(BigInteger n, BigInteger d, List<Frac> fracs) { if (n.equals(BigInteger.ZERO)) { return; } BigDecimal n2 = new BigDecimal(n); BigDecimal d2 = new BigDecimal(d); BigDecimal[] divRem = d2.divideAndRemainder(n2, MathContext.UNLIMITED); BigInteger div = divRem[0].toBigInteger(); if (divRem[1].compareTo(BigDecimal.ZERO) > 0) { div = div.add(BigInteger.ONE); } fracs.add(new Frac(BigInteger.ONE, div)); BigInteger n3 = d.negate().mod(n); if (n3.compareTo(BigInteger.ZERO) < 0) { n3 = n3.add(n); } BigInteger d3 = d.multiply(div); Frac f = new Frac(n3, d3); if (f.num.equals(BigInteger.ONE)) { fracs.add(f); return; } toEgyptian(f.num, f.denom, fracs); } } public static void main(String[] args) { List<Frac> fracs = List.of( new Frac(43, 48), new Frac(5, 121), new Frac(2014, 59) ); for (Frac frac : fracs) { List<Frac> list = frac.toEgyptian(); Frac first = list.get(0); if (first.denom.equals(BigInteger.ONE)) { System.out.printf("%s -> [%s] + ", frac, first); } else { System.out.printf("%s -> %s", frac, first); } for (int i = 1; i < list.size(); ++i) { System.out.printf(" + %s", list.get(i)); } System.out.println(); } for (Integer r : List.of(98, 998)) { if (r == 98) { System.out.println("\nFor proper fractions with 1 or 2 digits:"); } else { System.out.println("\nFor proper fractions with 1, 2 or 3 digits:"); } int maxSize = 0; List<Frac> maxSizeFracs = new ArrayList<>(); BigInteger maxDen = BigInteger.ZERO; List<Frac> maxDenFracs = new ArrayList<>(); boolean[][] sieve = new boolean[r + 1][]; for (int i = 0; i < r + 1; ++i) { sieve[i] = new boolean[r + 2]; } for (int i = 1; i < r; ++i) { for (int j = i + 1; j < r + 1; ++j) { if (sieve[i][j]) continue; Frac f = new Frac(i, j); List<Frac> list = f.toEgyptian(); int listSize = list.size(); if (listSize > maxSize) { maxSize = listSize; maxSizeFracs.clear(); maxSizeFracs.add(f); } else if (listSize == maxSize) { maxSizeFracs.add(f); } BigInteger listDen = list.get(list.size() - 1).denom; if (listDen.compareTo(maxDen) > 0) { maxDen = listDen; maxDenFracs.clear(); maxDenFracs.add(f); } else if (listDen.equals(maxDen)) { maxDenFracs.add(f); } if (i < r / 2) { int k = 2; while (true) { if (j * k > r + 1) break; sieve[i * k][j * k] = true; k++; } } } } System.out.printf(" largest number of items = %s\n", maxSize); System.out.printf("fraction(s) with this number : %s\n", maxSizeFracs); String md = maxDen.toString(); System.out.printf(" largest denominator = %s digits, ", md.length()); System.out.printf("%s...%s\n", md.substring(0, 20), md.substring(md.length() - 20, md.length())); System.out.printf("fraction(s) with this denominator : %s\n", maxDenFracs); } } }
def ef(fr) ans = [] if fr >= 1 return [[fr.to_i], Rational(0, 1)] if fr.denominator == 1 intfr = fr.to_i ans, fr = [intfr], fr - intfr end x, y = fr.numerator, fr.denominator while x != 1 ans << Rational(1, (1/fr).ceil) fr = Rational(-y % x, y * (1/fr).ceil) x, y = fr.numerator, fr.denominator end ans << fr end for fr in [Rational(43, 48), Rational(5, 121), Rational(2014, 59)] puts '%s => %s' % [fr, ef(fr).join(' + ')] end lenmax = denommax = [0] for b in 2..99 for a in 1...b fr = Rational(a,b) e = ef(fr) elen, edenom = e.length, e[-1].denominator lenmax = [elen, fr] if elen > lenmax[0] denommax = [edenom, fr] if edenom > denommax[0] end end puts 'Term max is %s with %i terms' % [lenmax[1], lenmax[0]] dstr = denommax[0].to_s puts 'Denominator max is %s with %i digits' % [denommax[1], dstr.size], dstr
Port the provided Java code into Ruby while preserving the original functionality.
import static java.lang.Math.*; import java.util.function.Function; public class Test { final static int N = 5; static double[] lroots = new double[N]; static double[] weight = new double[N]; static double[][] lcoef = new double[N + 1][N + 1]; static void legeCoef() { lcoef[0][0] = lcoef[1][1] = 1; for (int n = 2; n <= N; n++) { lcoef[n][0] = -(n - 1) * lcoef[n - 2][0] / n; for (int i = 1; i <= n; i++) { lcoef[n][i] = ((2 * n - 1) * lcoef[n - 1][i - 1] - (n - 1) * lcoef[n - 2][i]) / n; } } } static double legeEval(int n, double x) { double s = lcoef[n][n]; for (int i = n; i > 0; i--) s = s * x + lcoef[n][i - 1]; return s; } static double legeDiff(int n, double x) { return n * (x * legeEval(n, x) - legeEval(n - 1, x)) / (x * x - 1); } static void legeRoots() { double x, x1; for (int i = 1; i <= N; i++) { x = cos(PI * (i - 0.25) / (N + 0.5)); do { x1 = x; x -= legeEval(N, x) / legeDiff(N, x); } while (x != x1); lroots[i - 1] = x; x1 = legeDiff(N, x); weight[i - 1] = 2 / ((1 - x * x) * x1 * x1); } } static double legeInte(Function<Double, Double> f, double a, double b) { double c1 = (b - a) / 2, c2 = (b + a) / 2, sum = 0; for (int i = 0; i < N; i++) sum += weight[i] * f.apply(c1 * lroots[i] + c2); return c1 * sum; } public static void main(String[] args) { legeCoef(); legeRoots(); System.out.print("Roots: "); for (int i = 0; i < N; i++) System.out.printf(" %f", lroots[i]); System.out.print("\nWeight:"); for (int i = 0; i < N; i++) System.out.printf(" %f", weight[i]); System.out.printf("%nintegrating Exp(x) over [-3, 3]:%n\t%10.8f,%n" + "compared to actual%n\t%10.8f%n", legeInte(x -> exp(x), -3, 3), exp(3) - exp(-3)); } }
func legendre_pair((1), x) { (x, 1) } func legendre_pair( n, x) { var (m1, m2) = legendre_pair(n - 1, x) var u = (1 - 1/n) ((1 + u)*x*m1 - u*m2, m1) } func legendre((0), _) { 1 } func legendre( n, x) { [legendre_pair(n, x)][0] } func legendre_prime({ .is_zero }, _) { 0 } func legendre_prime({ .is_one }, _) { 1 } func legendre_prime(n, x) { var (m0, m1) = legendre_pair(n, x) (m1 - x*m0) * n / (1 - x**2) } func approximate_legendre_root(n, k) { var t = ((4*k - 1) / (4*n + 2)) (1 - ((n - 1)/(8 * n**3))) * cos(Num.pi * t) } func newton_raphson(f, f_prime, r, eps = 2e-16) { loop { var dr = (-f(r) / f_prime(r)) dr.abs >= eps || break r += dr } return r } func legendre_root(n, k) { newton_raphson(legendre.method(:call, n), legendre_prime.method(:call, n), approximate_legendre_root(n, k)) } func weight(n, r) { 2 / ((1 - r**2) * legendre_prime(n, r)**2) } func nodes(n) { gather { take(Pair(0, weight(n, 0))) if n.is_odd { |i| var r = legendre_root(n, i) var w = weight(n, r) take(Pair(r, w), Pair(-r, w)) }.each(1 .. (n >> 1)) } } func quadrature(n, f, a, b, nds = nodes(n)) { func scale(x) { (x*(b - a) + a + b) / 2 } (b - a) / 2 * nds.sum { .second * f(scale(.first)) } } [(5..10)..., 20].each { |i| printf("Gauss-Legendre %2d-point quadrature ∫₋₃⁺³ exp(x) dx ≈ %.15f\n", i, quadrature(i, {.exp}, -3, +3)) }
Translate this program into Ruby but keep the logic exactly as in Java.
import java.util.*; public class KdTree { private int dimensions_; private Node root_ = null; private Node best_ = null; private double bestDistance_ = 0; private int visited_ = 0; public KdTree(int dimensions, List<Node> nodes) { dimensions_ = dimensions; root_ = makeTree(nodes, 0, nodes.size(), 0); } public Node findNearest(Node target) { if (root_ == null) throw new IllegalStateException("Tree is empty!"); best_ = null; visited_ = 0; bestDistance_ = 0; nearest(root_, target, 0); return best_; } public int visited() { return visited_; } public double distance() { return Math.sqrt(bestDistance_); } private void nearest(Node root, Node target, int index) { if (root == null) return; ++visited_; double d = root.distance(target); if (best_ == null || d < bestDistance_) { bestDistance_ = d; best_ = root; } if (bestDistance_ == 0) return; double dx = root.get(index) - target.get(index); index = (index + 1) % dimensions_; nearest(dx > 0 ? root.left_ : root.right_, target, index); if (dx * dx >= bestDistance_) return; nearest(dx > 0 ? root.right_ : root.left_, target, index); } private Node makeTree(List<Node> nodes, int begin, int end, int index) { if (end <= begin) return null; int n = begin + (end - begin)/2; Node node = QuickSelect.select(nodes, begin, end - 1, n, new NodeComparator(index)); index = (index + 1) % dimensions_; node.left_ = makeTree(nodes, begin, n, index); node.right_ = makeTree(nodes, n + 1, end, index); return node; } private static class NodeComparator implements Comparator<Node> { private int index_; private NodeComparator(int index) { index_ = index; } public int compare(Node n1, Node n2) { return Double.compare(n1.get(index_), n2.get(index_)); } } public static class Node { private double[] coords_; private Node left_ = null; private Node right_ = null; public Node(double[] coords) { coords_ = coords; } public Node(double x, double y) { this(new double[]{x, y}); } public Node(double x, double y, double z) { this(new double[]{x, y, z}); } double get(int index) { return coords_[index]; } double distance(Node node) { double dist = 0; for (int i = 0; i < coords_.length; ++i) { double d = coords_[i] - node.coords_[i]; dist += d * d; } return dist; } public String toString() { StringBuilder s = new StringBuilder("("); for (int i = 0; i < coords_.length; ++i) { if (i > 0) s.append(", "); s.append(coords_[i]); } s.append(')'); return s.toString(); } } }
struct Kd_node { d, split, left, right, } struct Orthotope { min, max, } class Kd_tree(n, bounds) { method init { n = self.nk2(0, n); } method nk2(split, e) { return(nil) if (e.len <= 0); var exset = e.sort_by { _[split] } var m = (exset.len // 2); var d = exset[m]; while ((m+1 < exset.len) && (exset[m+1][split] == d[split])) { ++m; } var s2 = ((split + 1) % d.len); Kd_node(d: d, split: split, left: self.nk2(s2, exset.first(m)), right: self.nk2(s2, exset.last(m-1))); } } struct T3 { nearest, dist_sqd = Inf, nodes_visited = 0, } func find_nearest(k, t, p) { func nn(kd, target, hr, max_dist_sqd) { kd || return T3(nearest: [0]*k); var nodes_visited = 1; var s = kd.split; var pivot = kd.d; var left_hr = Orthotope(hr.min, hr.max); var right_hr = Orthotope(hr.min, hr.max); left_hr.max[s] = pivot[s]; right_hr.min[s] = pivot[s]; var nearer_kd; var further_kd; var nearer_hr; var further_hr; if (target[s] <= pivot[s]) { (nearer_kd, nearer_hr) = (kd.left, left_hr); (further_kd, further_hr) = (kd.right, right_hr); } else { (nearer_kd, nearer_hr) = (kd.right, right_hr); (further_kd, further_hr) = (kd.left, left_hr); } var n1 = nn(nearer_kd, target, nearer_hr, max_dist_sqd); var nearest = n1.nearest; var dist_sqd = n1.dist_sqd; nodes_visited += n1.nodes_visited; if (dist_sqd < max_dist_sqd) { max_dist_sqd = dist_sqd; } var d = (pivot[s] - target[s] -> sqr); if (d > max_dist_sqd) { return T3(nearest: nearest, dist_sqd: dist_sqd, nodes_visited: nodes_visited); } d = (pivot ~Z- target »sqr»() «+»); if (d < dist_sqd) { nearest = pivot; dist_sqd = d; max_dist_sqd = dist_sqd; } var n2 = nn(further_kd, target, further_hr, max_dist_sqd); nodes_visited += n2.nodes_visited; if (n2.dist_sqd < dist_sqd) { nearest = n2.nearest; dist_sqd = n2.dist_sqd; } T3(nearest: nearest, dist_sqd: dist_sqd, nodes_visited: nodes_visited); } return nn(t.n, p, t.bounds, Inf); } func show_nearest(k, heading, kd, p) { print <<-"END" Point: [ END var n = find_nearest(k, kd, p); print <<-"END" Nearest neighbor: [ Distance: Nodes visited: END } func random_point(k) { k.of { 1.rand } } func random_points(k, n) { n.of { random_point(k) } } var kd1 = Kd_tree([[2, 3],[5, 4],[9, 6],[4, 7],[8, 1],[7, 2]], Orthotope(min: [0, 0], max: [10, 10])); show_nearest(2, "Wikipedia example data", kd1, [9, 2]); var N = 1000 var t0 = Time.micro var kd2 = Kd_tree(random_points(3, N), Orthotope(min: [0,0,0], max: [1,1,1])) var t1 = Time.micro show_nearest(2, "k-d tree with kd2, random_point(3))
Translate this program into Ruby but keep the logic exactly as in Java.
import java.util.*; public class CutRectangle { private static int[][] dirs = {{0, -1}, {-1, 0}, {0, 1}, {1, 0}}; public static void main(String[] args) { cutRectangle(2, 2); cutRectangle(4, 3); } static void cutRectangle(int w, int h) { if (w % 2 == 1 && h % 2 == 1) return; int[][] grid = new int[h][w]; Stack<Integer> stack = new Stack<>(); int half = (w * h) / 2; long bits = (long) Math.pow(2, half) - 1; for (; bits > 0; bits -= 2) { for (int i = 0; i < half; i++) { int r = i / w; int c = i % w; grid[r][c] = (bits & (1 << i)) != 0 ? 1 : 0; grid[h - r - 1][w - c - 1] = 1 - grid[r][c]; } stack.push(0); grid[0][0] = 2; int count = 1; while (!stack.empty()) { int pos = stack.pop(); int r = pos / w; int c = pos % w; for (int[] dir : dirs) { int nextR = r + dir[0]; int nextC = c + dir[1]; if (nextR >= 0 && nextR < h && nextC >= 0 && nextC < w) { if (grid[nextR][nextC] == 1) { stack.push(nextR * w + nextC); grid[nextR][nextC] = 2; count++; } } } } if (count == half) { printResult(grid); } } } static void printResult(int[][] arr) { for (int[] a : arr) System.out.println(Arrays.toString(a)); System.out.println(); } }
def cut_it(h, w) if h.odd? return 0 if w.odd? h, w = w, h end return 1 if w == 1 nxt = [[w+1, 1, 0], [-w-1, -1, 0], [-1, 0, -1], [1, 0, 1]] blen = (h + 1) * (w + 1) - 1 grid = [false] * (blen + 1) walk = lambda do |y, x, count=0| return count+1 if y==0 or y==h or x==0 or x==w t = y * (w + 1) + x grid[t] = grid[blen - t] = true nxt.each do |nt, dy, dx| count += walk[y + dy, x + dx] unless grid[t + nt] end grid[t] = grid[blen - t] = false count end t = h / 2 * (w + 1) + w / 2 if w.odd? grid[t] = grid[t + 1] = true count = walk[h / 2, w / 2 - 1] count + walk[h / 2 - 1, w / 2] * 2 else grid[t] = true count = walk[h / 2, w / 2 - 1] return count * 2 if h == w count + walk[h / 2 - 1, w / 2] end end for w in 1..9 for h in 1..w puts "%d x %d: %d" % [w, h, cut_it(w, h)] if (w * h).even? end end
Translate the given Java code snippet into Ruby without altering its behavior.
import java.util.*; public class CutRectangle { private static int[][] dirs = {{0, -1}, {-1, 0}, {0, 1}, {1, 0}}; public static void main(String[] args) { cutRectangle(2, 2); cutRectangle(4, 3); } static void cutRectangle(int w, int h) { if (w % 2 == 1 && h % 2 == 1) return; int[][] grid = new int[h][w]; Stack<Integer> stack = new Stack<>(); int half = (w * h) / 2; long bits = (long) Math.pow(2, half) - 1; for (; bits > 0; bits -= 2) { for (int i = 0; i < half; i++) { int r = i / w; int c = i % w; grid[r][c] = (bits & (1 << i)) != 0 ? 1 : 0; grid[h - r - 1][w - c - 1] = 1 - grid[r][c]; } stack.push(0); grid[0][0] = 2; int count = 1; while (!stack.empty()) { int pos = stack.pop(); int r = pos / w; int c = pos % w; for (int[] dir : dirs) { int nextR = r + dir[0]; int nextC = c + dir[1]; if (nextR >= 0 && nextR < h && nextC >= 0 && nextC < w) { if (grid[nextR][nextC] == 1) { stack.push(nextR * w + nextC); grid[nextR][nextC] = 2; count++; } } } } if (count == half) { printResult(grid); } } } static void printResult(int[][] arr) { for (int[] a : arr) System.out.println(Arrays.toString(a)); System.out.println(); } }
def cut_it(h, w) if h.odd? return 0 if w.odd? h, w = w, h end return 1 if w == 1 nxt = [[w+1, 1, 0], [-w-1, -1, 0], [-1, 0, -1], [1, 0, 1]] blen = (h + 1) * (w + 1) - 1 grid = [false] * (blen + 1) walk = lambda do |y, x, count=0| return count+1 if y==0 or y==h or x==0 or x==w t = y * (w + 1) + x grid[t] = grid[blen - t] = true nxt.each do |nt, dy, dx| count += walk[y + dy, x + dx] unless grid[t + nt] end grid[t] = grid[blen - t] = false count end t = h / 2 * (w + 1) + w / 2 if w.odd? grid[t] = grid[t + 1] = true count = walk[h / 2, w / 2 - 1] count + walk[h / 2 - 1, w / 2] * 2 else grid[t] = true count = walk[h / 2, w / 2 - 1] return count * 2 if h == w count + walk[h / 2 - 1, w / 2] end end for w in 1..9 for h in 1..w puts "%d x %d: %d" % [w, h, cut_it(w, h)] if (w * h).even? end end
Please provide an equivalent version of this Java code in Ruby.
import java.awt.*; import java.awt.event.*; import java.util.*; import javax.swing.*; import javax.swing.Timer; public class ChaosGame extends JPanel { static class ColoredPoint extends Point { int colorIndex; ColoredPoint(int x, int y, int idx) { super(x, y); colorIndex = idx; } } Stack<ColoredPoint> stack = new Stack<>(); Point[] points = new Point[3]; Color[] colors = {Color.red, Color.green, Color.blue}; Random r = new Random(); public ChaosGame() { Dimension dim = new Dimension(640, 640); setPreferredSize(dim); setBackground(Color.white); int margin = 60; int size = dim.width - 2 * margin; points[0] = new Point(dim.width / 2, margin); points[1] = new Point(margin, size); points[2] = new Point(margin + size, size); stack.push(new ColoredPoint(-1, -1, 0)); new Timer(10, (ActionEvent e) -> { if (stack.size() < 50_000) { for (int i = 0; i < 1000; i++) addPoint(); repaint(); } }).start(); } private void addPoint() { try { int colorIndex = r.nextInt(3); Point p1 = stack.peek(); Point p2 = points[colorIndex]; stack.add(halfwayPoint(p1, p2, colorIndex)); } catch (EmptyStackException e) { e.printStackTrace(); } } void drawPoints(Graphics2D g) { for (ColoredPoint p : stack) { g.setColor(colors[p.colorIndex]); g.fillOval(p.x, p.y, 1, 1); } } ColoredPoint halfwayPoint(Point a, Point b, int idx) { return new ColoredPoint((a.x + b.x) / 2, (a.y + b.y) / 2, idx); } @Override public void paintComponent(Graphics gg) { super.paintComponent(gg); Graphics2D g = (Graphics2D) gg; g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); drawPoints(g); } public static void main(String[] args) { SwingUtilities.invokeLater(() -> { JFrame f = new JFrame(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setTitle("Chaos Game"); f.setResizable(false); f.add(new ChaosGame(), BorderLayout.CENTER); f.pack(); f.setLocationRelativeTo(null); f.setVisible(true); }); } }
require('Imager') var width = 600 var height = 600 var points = [ [width//2, 0], [ 0, height-1], [height-1, height-1], ] var img = %O|Imager|.new( xsize => width, ysize => height, ) var color = %O|Imager::Color|.new(' var r = [(width-1).irand, (height-1).irand] 30000.times { var p = points.rand r[] = ( (p[0] + r[0]) // 2, (p[1] + r[1]) // 2, ) img.setpixel( x => r[0], y => r[1], color => color, ) } img.write(file => 'chaos_game.png')
Ensure the translated Ruby code behaves exactly like the original Java snippet.
import java.awt.*; import java.awt.event.*; import java.util.*; import javax.swing.*; import javax.swing.Timer; public class ChaosGame extends JPanel { static class ColoredPoint extends Point { int colorIndex; ColoredPoint(int x, int y, int idx) { super(x, y); colorIndex = idx; } } Stack<ColoredPoint> stack = new Stack<>(); Point[] points = new Point[3]; Color[] colors = {Color.red, Color.green, Color.blue}; Random r = new Random(); public ChaosGame() { Dimension dim = new Dimension(640, 640); setPreferredSize(dim); setBackground(Color.white); int margin = 60; int size = dim.width - 2 * margin; points[0] = new Point(dim.width / 2, margin); points[1] = new Point(margin, size); points[2] = new Point(margin + size, size); stack.push(new ColoredPoint(-1, -1, 0)); new Timer(10, (ActionEvent e) -> { if (stack.size() < 50_000) { for (int i = 0; i < 1000; i++) addPoint(); repaint(); } }).start(); } private void addPoint() { try { int colorIndex = r.nextInt(3); Point p1 = stack.peek(); Point p2 = points[colorIndex]; stack.add(halfwayPoint(p1, p2, colorIndex)); } catch (EmptyStackException e) { e.printStackTrace(); } } void drawPoints(Graphics2D g) { for (ColoredPoint p : stack) { g.setColor(colors[p.colorIndex]); g.fillOval(p.x, p.y, 1, 1); } } ColoredPoint halfwayPoint(Point a, Point b, int idx) { return new ColoredPoint((a.x + b.x) / 2, (a.y + b.y) / 2, idx); } @Override public void paintComponent(Graphics gg) { super.paintComponent(gg); Graphics2D g = (Graphics2D) gg; g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); drawPoints(g); } public static void main(String[] args) { SwingUtilities.invokeLater(() -> { JFrame f = new JFrame(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setTitle("Chaos Game"); f.setResizable(false); f.add(new ChaosGame(), BorderLayout.CENTER); f.pack(); f.setLocationRelativeTo(null); f.setVisible(true); }); } }
require('Imager') var width = 600 var height = 600 var points = [ [width//2, 0], [ 0, height-1], [height-1, height-1], ] var img = %O|Imager|.new( xsize => width, ysize => height, ) var color = %O|Imager::Color|.new(' var r = [(width-1).irand, (height-1).irand] 30000.times { var p = points.rand r[] = ( (p[0] + r[0]) // 2, (p[1] + r[1]) // 2, ) img.setpixel( x => r[0], y => r[1], color => color, ) } img.write(file => 'chaos_game.png')
Preserve the algorithm and functionality while converting the code from Java to Ruby.
import java.util.Arrays; public class GroupStage{ static String[] games = {"12", "13", "14", "23", "24", "34"}; static String results = "000000"; private static boolean nextResult(){ if(results.equals("222222")) return false; int res = Integer.parseInt(results, 3) + 1; results = Integer.toString(res, 3); while(results.length() < 6) results = "0" + results; return true; } public static void main(String[] args){ int[][] points = new int[4][10]; do{ int[] records = {0,0,0,0}; for(int i = 0; i < 6; i++){ switch(results.charAt(i)){ case '2': records[games[i].charAt(0) - '1'] += 3; break; case '1': records[games[i].charAt(0) - '1']++; records[games[i].charAt(1) - '1']++; break; case '0': records[games[i].charAt(1) - '1'] += 3; break; } } Arrays.sort(records); points[0][records[0]]++; points[1][records[1]]++; points[2][records[2]]++; points[3][records[3]]++; }while(nextResult()); System.out.println("First place: " + Arrays.toString(points[3])); System.out.println("Second place: " + Arrays.toString(points[2])); System.out.println("Third place: " + Arrays.toString(points[1])); System.out.println("Fourth place: " + Arrays.toString(points[0])); } }
teams = [:a, :b, :c, :d] matches = teams.combination(2).to_a outcomes = [:win, :draw, :loss] gains = {win:[3,0], draw:[1,1], loss:[0,3]} places_histogram = Array.new(4) {Array.new(10,0)} outcomes.repeated_permutation(6).each do |outcome| results = Hash.new(0) outcome.zip(matches).each do |decision, (team1, team2)| results[team1] += gains[decision][0] results[team2] += gains[decision][1] end results.values.sort.reverse.each_with_index do |points, place| places_histogram[place][points] += 1 end end fmt = "%s :" + "%4s"*10 puts fmt % [" ", *0..9] puts fmt % ["-", *["---"]*10] places_histogram.each.with_index(1) {|hist,place| puts fmt % [place, *hist]}
Transform the following Java implementation into Ruby, maintaining the same output and logic.
import java.util.Stack; public class ShuntingYard { public static void main(String[] args) { String infix = "3 + 4 * 2 / ( 1 - 5 ) ^ 2 ^ 3"; System.out.printf("infix: %s%n", infix); System.out.printf("postfix: %s%n", infixToPostfix(infix)); } static String infixToPostfix(String infix) { final String ops = "-+/*^"; StringBuilder sb = new StringBuilder(); Stack<Integer> s = new Stack<>(); for (String token : infix.split("\\s")) { if (token.isEmpty()) continue; char c = token.charAt(0); int idx = ops.indexOf(c); if (idx != -1) { if (s.isEmpty()) s.push(idx); else { while (!s.isEmpty()) { int prec2 = s.peek() / 2; int prec1 = idx / 2; if (prec2 > prec1 || (prec2 == prec1 && c != '^')) sb.append(ops.charAt(s.pop())).append(' '); else break; } s.push(idx); } } else if (c == '(') { s.push(-2); } else if (c == ')') { while (s.peek() != -2) sb.append(ops.charAt(s.pop())).append(' '); s.pop(); } else { sb.append(token).append(' '); } } while (!s.isEmpty()) sb.append(ops.charAt(s.pop())).append(' '); return sb.toString(); } }
rpn = RPNExpression.from_infix("3 + 4 * 2 / ( 1 - 5 ) ^ 2 ^ 3")
Port the provided Java code into Ruby while preserving the original functionality.
public final class ImprovedNoise { static public double noise(double x, double y, double z) { int X = (int)Math.floor(x) & 255, Y = (int)Math.floor(y) & 255, Z = (int)Math.floor(z) & 255; x -= Math.floor(x); y -= Math.floor(y); z -= Math.floor(z); double u = fade(x), v = fade(y), w = fade(z); int A = p[X ]+Y, AA = p[A]+Z, AB = p[A+1]+Z, B = p[X+1]+Y, BA = p[B]+Z, BB = p[B+1]+Z; return lerp(w, lerp(v, lerp(u, grad(p[AA ], x , y , z ), grad(p[BA ], x-1, y , z )), lerp(u, grad(p[AB ], x , y-1, z ), grad(p[BB ], x-1, y-1, z ))), lerp(v, lerp(u, grad(p[AA+1], x , y , z-1 ), grad(p[BA+1], x-1, y , z-1 )), lerp(u, grad(p[AB+1], x , y-1, z-1 ), grad(p[BB+1], x-1, y-1, z-1 )))); } static double fade(double t) { return t * t * t * (t * (t * 6 - 15) + 10); } static double lerp(double t, double a, double b) { return a + t * (b - a); } static double grad(int hash, double x, double y, double z) { int h = hash & 15; double u = h<8 ? x : y, v = h<4 ? y : h==12||h==14 ? x : z; return ((h&1) == 0 ? u : -u) + ((h&2) == 0 ? v : -v); } static final int p[] = new int[512], permutation[] = { 151,160,137,91,90,15, 131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23, 190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33, 88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166, 77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244, 102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196, 135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123, 5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42, 223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9, 129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228, 251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107, 49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254, 138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180 }; static { for (int i=0; i < 256 ; i++) p[256+i] = p[i] = permutation[i]; } }
const p = (%w'47 4G 3T 2J 2I F 3N D 5L 2N 2O 1H 5E 6H 7 69 3W 10 2V U 1X 3Y 8 2R 11 6O L A N 5A 6 44 6V 3C 6I 23 0 Q 5H 1Q 2M 70 63 5N 39 Z B W 1L 4X X 2G 6L 45 1K 2F 4U K 3H 3S 4R 4O 1W 4V 22 4L 1Z 3Q 3V 1C R 4M 25 42 4E 6F 2B 33 6D 3E 1O 5V 3P 6E 64 2X 2K 15 1J 1A 6T 14 6S 2U 3Z 1I 1T P 1R 4H 1 60 28 21 5T 24 3O 57 5S 2H I 4P 5K 5G 3R 3M 38 58 4F 2E 4K 2S 31 5I 4T 56 3 1S 1G 61 6A 6Y 3G 3F 5 5M 12 43 3A 3I 73 2A 2D 5W 5R 5Q 1N 6B 1B G 1M H 52 59 S 16 67 53 4Q 5X 3B 6W 48 2 18 4A 4J 1Y 65 49 2T 4B 4N 17 4S 9 3L M 13 71 J 2Q 30 32 27 35 68 6G 4Y 55 34 2W 62 6U 2P 6C 6Z Y 6Q 5D 6M 5U 40 C 5B 4Z 4I 6P 29 1F 41 6J 6X E 6N 2Z 1D 5C 5Y V 51 5J 2Y 4D 54 2C 5O 4W 37 3D 1E 19 3J 4 46 72 3U 6K 5P 2L 66 36 1V T O 20 6R 3X 3K 5F 26 1U 5Z 1P 4C 50' * 2 -> map {|n| Num(n, 36) }) func fade(n) { n * n * n * (n * (n * 6 - 15) + 10) } func lerp(t, a, b) { a + t*(b-a) } func grad(h, x, y, z) { h &= 15 var u = (h < 8 ? x : y) var v = (h < 4 ? y : (h ~~ [12,14] ? x : z)) (h&1 ? -u : u) + (h&2 ? -v : v) } func noise(x, y, z) { var(X, Y, Z) = [x, y, z].map { .floor & 255 }... var (u, v, w) = [x-=X, y-=Y, z-=Z].map { fade(_) }... var (AA, AB) = with(p[X] + Y) {|i| (p[i] + Z, p[i+1] + Z) } var (BA, BB) = with(p[X+1] + Y) {|i| (p[i] + Z, p[i+1] + Z) } lerp(w, lerp(v, lerp(u, grad(p[AA ], x , y , z ), grad(p[BA ], x-1, y , z )), lerp(u, grad(p[AB ], x , y-1, z ), grad(p[BB ], x-1, y-1, z ))), lerp(v, lerp(u, grad(p[AA+1], x , y , z-1), grad(p[BA+1], x-1, y , z-1)), lerp(u, grad(p[AB+1], x , y-1, z-1), grad(p[BB+1], x-1, y-1, z-1)))) } say noise(3.14, 42, 7)
Convert the following code from Java to Ruby, ensuring the logic remains intact.
package astar; import java.util.List; import java.util.ArrayList; import java.util.Collections; import java.util.PriorityQueue; import java.util.Comparator; import java.util.LinkedList; import java.util.Queue; class AStar { private final List<Node> open; private final List<Node> closed; private final List<Node> path; private final int[][] maze; private Node now; private final int xstart; private final int ystart; private int xend, yend; private final boolean diag; static class Node implements Comparable { public Node parent; public int x, y; public double g; public double h; Node(Node parent, int xpos, int ypos, double g, double h) { this.parent = parent; this.x = xpos; this.y = ypos; this.g = g; this.h = h; } @Override public int compareTo(Object o) { Node that = (Node) o; return (int)((this.g + this.h) - (that.g + that.h)); } } AStar(int[][] maze, int xstart, int ystart, boolean diag) { this.open = new ArrayList<>(); this.closed = new ArrayList<>(); this.path = new ArrayList<>(); this.maze = maze; this.now = new Node(null, xstart, ystart, 0, 0); this.xstart = xstart; this.ystart = ystart; this.diag = diag; } public List<Node> findPathTo(int xend, int yend) { this.xend = xend; this.yend = yend; this.closed.add(this.now); addNeigborsToOpenList(); while (this.now.x != this.xend || this.now.y != this.yend) { if (this.open.isEmpty()) { return null; } this.now = this.open.get(0); this.open.remove(0); this.closed.add(this.now); addNeigborsToOpenList(); } this.path.add(0, this.now); while (this.now.x != this.xstart || this.now.y != this.ystart) { this.now = this.now.parent; this.path.add(0, this.now); } return this.path; } public void expandAStar(int[][] maze, int xstart, int ystart, boolean diag){ Queue<Mazecoord> exploreNodes = new LinkedList<Mazecoord>(); if(maze[stateNode.getR()][stateNode.getC()] == 2){ if(isNodeILegal(stateNode, stateNode.expandDirection())){ exploreNodes.add(stateNode.expandDirection()); } } public void AStarSearch(){ this.start.setCostToGoal(this.start.calculateCost(this.goal)); this.start.setPathCost(0); this.start.setAStartCost(this.start.getPathCost() + this.start.getCostToGoal()); Mazecoord intialNode = this.start; Mazecoord stateNode = intialNode; frontier.add(intialNode); while (true){ if(frontier.isEmpty()){ System.out.println("fail"); System.out.println(explored.size()); System.exit(-1); } } public int calculateCost(Mazecoord goal){ int rState = this.getR(); int rGoal = goal.getR(); int diffR = rState - rGoal; int diffC = this.getC() - goal.getC(); if(diffR * diffC > 0) { return Math.abs(diffR) + Math.abs(diffC); } else { return Math.max(Math.abs(diffR), Math.abs(diffC)); } } public Coord getFather(){ return this.father; } public void setFather(Mazecoord node){ this.father = node; } public int getAStartCost() { return AStartCost; } public void setAStartCost(int aStartCost) { AStartCost = aStartCost; } public int getCostToGoal() { return costToGoal; } public void setCostToGoal(int costToGoal) { this.costToGoal = costToGoal; } private double distance(int dx, int dy) { if (this.diag) { return Math.hypot(this.now.x + dx - this.xend, this.now.y + dy - this.yend); } else { return Math.abs(this.now.x + dx - this.xend) + Math.abs(this.now.y + dy - this.yend); } } private void addNeigborsToOpenList() { Node node; for (int x = -1; x <= 1; x++) { for (int y = -1; y <= 1; y++) { if (!this.diag && x != 0 && y != 0) { continue; } node = new Node(this.now, this.now.x + x, this.now.y + y, this.now.g, this.distance(x, y)); if ((x != 0 || y != 0) && this.now.x + x >= 0 && this.now.x + x < this.maze[0].length && this.now.y + y >= 0 && this.now.y + y < this.maze.length && this.maze[this.now.y + y][this.now.x + x] != -1 && !findNeighborInList(this.open, node) && !findNeighborInList(this.closed, node)) { node.g = node.parent.g + 1.; node.g += maze[this.now.y + y][this.now.x + x]; this.open.add(node); } } } Collections.sort(this.open); } public static void main(String[] args) { int[][] maze = { { 0, 0, 0, 0, 0, 0, 0, 0}, { 0, 0, 0, 0, 0, 0, 0, 0}, { 0, 0, 0,100,100,100, 0, 0}, { 0, 0, 0, 0, 0,100, 0, 0}, { 0, 0,100, 0, 0,100, 0, 0}, { 0, 0,100, 0, 0,100, 0, 0}, { 0, 0,100,100,100,100, 0, 0}, { 0, 0, 0, 0, 0, 0, 0, 0}, }; AStar as = new AStar(maze, 0, 0, true); List<Node> path = as.findPathTo(7, 7); if (path != null) { path.forEach((n) -> { System.out.print("[" + n.x + ", " + n.y + "] "); maze[n.y][n.x] = -1; }); System.out.printf("\nTotal cost: %.02f\n", path.get(path.size() - 1).g); for (int[] maze_row : maze) { for (int maze_entry : maze_row) { switch (maze_entry) { case 0: System.out.print("_"); break; case -1: System.out.print("*"); break; default: System.out.print("#"); } } System.out.println(); } } } }
class AStarGraph { has barriers = [ [2,4],[2,5],[2,6],[3,6],[4,6],[5,6],[5,5],[5,4],[5,3],[5,2],[4,2],[3,2] ] method heuristic(start, goal) { var (D1 = 1, D2 = 1) var dx = abs(start[0] - goal[0]) var dy = abs(start[1] - goal[1]) (D1 * (dx + dy)) + ((D2 - 2*D1) * Math.min(dx, dy)) } method get_vertex_neighbours(pos) { gather { for dx, dy in [[1,0],[-1,0],[0,1],[0,-1],[1,1],[-1,1],[1,-1],[-1,-1]] { var x2 = (pos[0] + dx) var y2 = (pos[1] + dy) (x2<0 || x2>7 || y2<0 || y2>7) && next take([x2, y2]) } } } method move_cost(_a, b) { barriers.contains(b) ? 100 : 1 } } func AStarSearch(start, end, graph) { var G = Hash() var F = Hash() G{start} = 0 F{start} = graph.heuristic(start, end) var closedVertices = [] var openVertices = [start] var cameFrom = Hash() while (openVertices) { var current = nil var currentFscore = Inf for pos in openVertices { if (F{pos} < currentFscore) { currentFscore = F{pos} current = pos } } if (current == end) { var path = [current] while (cameFrom.contains(current)) { current = cameFrom{current} path << current } path.flip! return (path, F{end}) } openVertices.remove(current) closedVertices.append(current) for neighbour in (graph.get_vertex_neighbours(current)) { if (closedVertices.contains(neighbour)) { next } var candidateG = (G{current} + graph.move_cost(current, neighbour)) if (!openVertices.contains(neighbour)) { openVertices.append(neighbour) } elsif (candidateG >= G{neighbour}) { next } cameFrom{neighbour} = current G{neighbour} = candidateG var H = graph.heuristic(neighbour, end) F{neighbour} = (G{neighbour} + H) } } die "A* failed to find a solution" } var graph = AStarGraph() var (route, cost) = AStarSearch([0,0], [7,7], graph) var w = 10 var h = 10 var grid = h.of { w.of { "." } } for y in (^h) { grid[y][0] = "█"; grid[y][-1] = "█" } for x in (^w) { grid[0][x] = "█"; grid[-1][x] = "█" } for x,y in (graph.barriers) { grid[x+1][y+1] = "█" } for x,y in (route) { grid[x+1][y+1] = "x" } grid.each { .join.say } say "Path cost
Ensure the translated Ruby code behaves exactly like the original Java snippet.
package astar; import java.util.List; import java.util.ArrayList; import java.util.Collections; import java.util.PriorityQueue; import java.util.Comparator; import java.util.LinkedList; import java.util.Queue; class AStar { private final List<Node> open; private final List<Node> closed; private final List<Node> path; private final int[][] maze; private Node now; private final int xstart; private final int ystart; private int xend, yend; private final boolean diag; static class Node implements Comparable { public Node parent; public int x, y; public double g; public double h; Node(Node parent, int xpos, int ypos, double g, double h) { this.parent = parent; this.x = xpos; this.y = ypos; this.g = g; this.h = h; } @Override public int compareTo(Object o) { Node that = (Node) o; return (int)((this.g + this.h) - (that.g + that.h)); } } AStar(int[][] maze, int xstart, int ystart, boolean diag) { this.open = new ArrayList<>(); this.closed = new ArrayList<>(); this.path = new ArrayList<>(); this.maze = maze; this.now = new Node(null, xstart, ystart, 0, 0); this.xstart = xstart; this.ystart = ystart; this.diag = diag; } public List<Node> findPathTo(int xend, int yend) { this.xend = xend; this.yend = yend; this.closed.add(this.now); addNeigborsToOpenList(); while (this.now.x != this.xend || this.now.y != this.yend) { if (this.open.isEmpty()) { return null; } this.now = this.open.get(0); this.open.remove(0); this.closed.add(this.now); addNeigborsToOpenList(); } this.path.add(0, this.now); while (this.now.x != this.xstart || this.now.y != this.ystart) { this.now = this.now.parent; this.path.add(0, this.now); } return this.path; } public void expandAStar(int[][] maze, int xstart, int ystart, boolean diag){ Queue<Mazecoord> exploreNodes = new LinkedList<Mazecoord>(); if(maze[stateNode.getR()][stateNode.getC()] == 2){ if(isNodeILegal(stateNode, stateNode.expandDirection())){ exploreNodes.add(stateNode.expandDirection()); } } public void AStarSearch(){ this.start.setCostToGoal(this.start.calculateCost(this.goal)); this.start.setPathCost(0); this.start.setAStartCost(this.start.getPathCost() + this.start.getCostToGoal()); Mazecoord intialNode = this.start; Mazecoord stateNode = intialNode; frontier.add(intialNode); while (true){ if(frontier.isEmpty()){ System.out.println("fail"); System.out.println(explored.size()); System.exit(-1); } } public int calculateCost(Mazecoord goal){ int rState = this.getR(); int rGoal = goal.getR(); int diffR = rState - rGoal; int diffC = this.getC() - goal.getC(); if(diffR * diffC > 0) { return Math.abs(diffR) + Math.abs(diffC); } else { return Math.max(Math.abs(diffR), Math.abs(diffC)); } } public Coord getFather(){ return this.father; } public void setFather(Mazecoord node){ this.father = node; } public int getAStartCost() { return AStartCost; } public void setAStartCost(int aStartCost) { AStartCost = aStartCost; } public int getCostToGoal() { return costToGoal; } public void setCostToGoal(int costToGoal) { this.costToGoal = costToGoal; } private double distance(int dx, int dy) { if (this.diag) { return Math.hypot(this.now.x + dx - this.xend, this.now.y + dy - this.yend); } else { return Math.abs(this.now.x + dx - this.xend) + Math.abs(this.now.y + dy - this.yend); } } private void addNeigborsToOpenList() { Node node; for (int x = -1; x <= 1; x++) { for (int y = -1; y <= 1; y++) { if (!this.diag && x != 0 && y != 0) { continue; } node = new Node(this.now, this.now.x + x, this.now.y + y, this.now.g, this.distance(x, y)); if ((x != 0 || y != 0) && this.now.x + x >= 0 && this.now.x + x < this.maze[0].length && this.now.y + y >= 0 && this.now.y + y < this.maze.length && this.maze[this.now.y + y][this.now.x + x] != -1 && !findNeighborInList(this.open, node) && !findNeighborInList(this.closed, node)) { node.g = node.parent.g + 1.; node.g += maze[this.now.y + y][this.now.x + x]; this.open.add(node); } } } Collections.sort(this.open); } public static void main(String[] args) { int[][] maze = { { 0, 0, 0, 0, 0, 0, 0, 0}, { 0, 0, 0, 0, 0, 0, 0, 0}, { 0, 0, 0,100,100,100, 0, 0}, { 0, 0, 0, 0, 0,100, 0, 0}, { 0, 0,100, 0, 0,100, 0, 0}, { 0, 0,100, 0, 0,100, 0, 0}, { 0, 0,100,100,100,100, 0, 0}, { 0, 0, 0, 0, 0, 0, 0, 0}, }; AStar as = new AStar(maze, 0, 0, true); List<Node> path = as.findPathTo(7, 7); if (path != null) { path.forEach((n) -> { System.out.print("[" + n.x + ", " + n.y + "] "); maze[n.y][n.x] = -1; }); System.out.printf("\nTotal cost: %.02f\n", path.get(path.size() - 1).g); for (int[] maze_row : maze) { for (int maze_entry : maze_row) { switch (maze_entry) { case 0: System.out.print("_"); break; case -1: System.out.print("*"); break; default: System.out.print("#"); } } System.out.println(); } } } }
class AStarGraph { has barriers = [ [2,4],[2,5],[2,6],[3,6],[4,6],[5,6],[5,5],[5,4],[5,3],[5,2],[4,2],[3,2] ] method heuristic(start, goal) { var (D1 = 1, D2 = 1) var dx = abs(start[0] - goal[0]) var dy = abs(start[1] - goal[1]) (D1 * (dx + dy)) + ((D2 - 2*D1) * Math.min(dx, dy)) } method get_vertex_neighbours(pos) { gather { for dx, dy in [[1,0],[-1,0],[0,1],[0,-1],[1,1],[-1,1],[1,-1],[-1,-1]] { var x2 = (pos[0] + dx) var y2 = (pos[1] + dy) (x2<0 || x2>7 || y2<0 || y2>7) && next take([x2, y2]) } } } method move_cost(_a, b) { barriers.contains(b) ? 100 : 1 } } func AStarSearch(start, end, graph) { var G = Hash() var F = Hash() G{start} = 0 F{start} = graph.heuristic(start, end) var closedVertices = [] var openVertices = [start] var cameFrom = Hash() while (openVertices) { var current = nil var currentFscore = Inf for pos in openVertices { if (F{pos} < currentFscore) { currentFscore = F{pos} current = pos } } if (current == end) { var path = [current] while (cameFrom.contains(current)) { current = cameFrom{current} path << current } path.flip! return (path, F{end}) } openVertices.remove(current) closedVertices.append(current) for neighbour in (graph.get_vertex_neighbours(current)) { if (closedVertices.contains(neighbour)) { next } var candidateG = (G{current} + graph.move_cost(current, neighbour)) if (!openVertices.contains(neighbour)) { openVertices.append(neighbour) } elsif (candidateG >= G{neighbour}) { next } cameFrom{neighbour} = current G{neighbour} = candidateG var H = graph.heuristic(neighbour, end) F{neighbour} = (G{neighbour} + H) } } die "A* failed to find a solution" } var graph = AStarGraph() var (route, cost) = AStarSearch([0,0], [7,7], graph) var w = 10 var h = 10 var grid = h.of { w.of { "." } } for y in (^h) { grid[y][0] = "█"; grid[y][-1] = "█" } for x in (^w) { grid[0][x] = "█"; grid[-1][x] = "█" } for x,y in (graph.barriers) { grid[x+1][y+1] = "█" } for x,y in (route) { grid[x+1][y+1] = "x" } grid.each { .join.say } say "Path cost
Translate the given Java code snippet into Ruby without altering its behavior.
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); } }
require "set" require "big" def add_reverse(num, max_iter=1000) num = num.to_big_i nums = [] of BigInt (1..max_iter).each_with_object(Set.new([num])) do |_, nums| num += reverse_int(num) nums << num return nums if palindrome?(num) end end def palindrome?(num) num == reverse_int(num) end def reverse_int(num) num.to_s.reverse.to_big_i end def split_roots_from_relateds(roots_and_relateds) roots = roots_and_relateds.dup i = 1 while i < roots.size this = roots[i] if roots[0...i].any?{ |prev| this.intersects?(prev) } roots.delete_at(i) else i += 1 end end root = roots.map{ |each_set| each_set.min } related = roots_and_relateds.map{ |each_set| each_set.min } related = related.reject{ |n| root.includes?(n) } return root, related end def find_lychrel(maxn, max_reversions) series = (1..maxn).map{ |n| add_reverse(n, max_reversions*2) } roots_and_relateds = series.select{ |s| s.size > max_reversions } split_roots_from_relateds(roots_and_relateds) end maxn, reversion_limit = 10000, 500 puts "Calculations using n = 1.. lychrel, l_related = find_lychrel(maxn, reversion_limit) puts " Number of Lychrel numbers: puts " Lychrel numbers: puts " Number of Lychrel related: pals = (lychrel + l_related).select{|x| palindrome?(x)}.sort puts " Number of Lychrel palindromes: puts " Lychrel palindromes:
Convert this Java snippet to Ruby and keep its semantics consistent.
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); } }
require "set" require "big" def add_reverse(num, max_iter=1000) num = num.to_big_i nums = [] of BigInt (1..max_iter).each_with_object(Set.new([num])) do |_, nums| num += reverse_int(num) nums << num return nums if palindrome?(num) end end def palindrome?(num) num == reverse_int(num) end def reverse_int(num) num.to_s.reverse.to_big_i end def split_roots_from_relateds(roots_and_relateds) roots = roots_and_relateds.dup i = 1 while i < roots.size this = roots[i] if roots[0...i].any?{ |prev| this.intersects?(prev) } roots.delete_at(i) else i += 1 end end root = roots.map{ |each_set| each_set.min } related = roots_and_relateds.map{ |each_set| each_set.min } related = related.reject{ |n| root.includes?(n) } return root, related end def find_lychrel(maxn, max_reversions) series = (1..maxn).map{ |n| add_reverse(n, max_reversions*2) } roots_and_relateds = series.select{ |s| s.size > max_reversions } split_roots_from_relateds(roots_and_relateds) end maxn, reversion_limit = 10000, 500 puts "Calculations using n = 1.. lychrel, l_related = find_lychrel(maxn, reversion_limit) puts " Number of Lychrel numbers: puts " Lychrel numbers: puts " Number of Lychrel related: pals = (lychrel + l_related).select{|x| palindrome?(x)}.sort puts " Number of Lychrel palindromes: puts " Lychrel palindromes:
Translate the given Java code snippet into Ruby without altering its behavior.
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; } } }
var equationtext = <<'EOT' pi/4 = arctan(1/2) + arctan(1/3) pi/4 = 2*arctan(1/3) + arctan(1/7) pi/4 = 4*arctan(1/5) - arctan(1/239) pi/4 = 5*arctan(1/7) + 2*arctan(3/79) pi/4 = 5*arctan(29/278) + 7*arctan(3/79) pi/4 = arctan(1/2) + arctan(1/5) + arctan(1/8) pi/4 = 4*arctan(1/5) - arctan(1/70) + arctan(1/99) pi/4 = 5*arctan(1/7) + 4*arctan(1/53) + 2*arctan(1/4443) pi/4 = 6*arctan(1/8) + 2*arctan(1/57) + arctan(1/239) pi/4 = 8*arctan(1/10) - arctan(1/239) - 4*arctan(1/515) pi/4 = 12*arctan(1/18) + 8*arctan(1/57) - 5*arctan(1/239) pi/4 = 16*arctan(1/21) + 3*arctan(1/239) + 4*arctan(3/1042) pi/4 = 22*arctan(1/28) + 2*arctan(1/443) - 5*arctan(1/1393) - 10*arctan(1/11018) pi/4 = 22*arctan(1/38) + 17*arctan(7/601) + 10*arctan(7/8149) pi/4 = 44*arctan(1/57) + 7*arctan(1/239) - 12*arctan(1/682) + 24*arctan(1/12943) pi/4 = 88*arctan(1/172) + 51*arctan(1/239) + 32*arctan(1/682) + 44*arctan(1/5357) + 68*arctan(1/12943) pi/4 = 88*arctan(1/172) + 51*arctan(1/239) + 32*arctan(1/682) + 44*arctan(1/5357) + 68*arctan(1/12944) EOT func parse_eqn(equation) { static eqn_re = %r{ (^ \s* pi/4 \s* = \s* )? (?: \s* ( [-+] )? \s* (?: ( \d+ ) \s* \*)? \s* arctan\((.*?)\) )}x gather { for lhs,sign,mult,rat in (equation.findall(eqn_re)) { take([ [+1, -1][sign == '-'] * (mult ? Num(mult) : 1), Num(rat) ]) } } } func tanEval(coef, f) { return f if (coef == 1) return -tanEval(-coef, f) if (coef < 0) var ca = coef>>1 var cb = (coef - ca) var (a, b) = (tanEval(ca, f), tanEval(cb, f)) (a + b) / (1 - a*b) } func tans(xs) { var xslen = xs.len return tanEval(xs[0]...) if (xslen == 1) var (aa, bb) = xs.part(xslen>>1) var (a, b) = (tans(aa), tans(bb)) (a + b) / (1 - a*b) } var machins = equationtext.lines.map(parse_eqn) for machin,eqn in (machins ~Z equationtext.lines) { var ans = tans(machin) printf("%5s: %s\n", (ans == 1 ? 'OK' : 'ERROR'), eqn) }
Change the following Java code into Ruby without altering its purpose.
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; } } }
var equationtext = <<'EOT' pi/4 = arctan(1/2) + arctan(1/3) pi/4 = 2*arctan(1/3) + arctan(1/7) pi/4 = 4*arctan(1/5) - arctan(1/239) pi/4 = 5*arctan(1/7) + 2*arctan(3/79) pi/4 = 5*arctan(29/278) + 7*arctan(3/79) pi/4 = arctan(1/2) + arctan(1/5) + arctan(1/8) pi/4 = 4*arctan(1/5) - arctan(1/70) + arctan(1/99) pi/4 = 5*arctan(1/7) + 4*arctan(1/53) + 2*arctan(1/4443) pi/4 = 6*arctan(1/8) + 2*arctan(1/57) + arctan(1/239) pi/4 = 8*arctan(1/10) - arctan(1/239) - 4*arctan(1/515) pi/4 = 12*arctan(1/18) + 8*arctan(1/57) - 5*arctan(1/239) pi/4 = 16*arctan(1/21) + 3*arctan(1/239) + 4*arctan(3/1042) pi/4 = 22*arctan(1/28) + 2*arctan(1/443) - 5*arctan(1/1393) - 10*arctan(1/11018) pi/4 = 22*arctan(1/38) + 17*arctan(7/601) + 10*arctan(7/8149) pi/4 = 44*arctan(1/57) + 7*arctan(1/239) - 12*arctan(1/682) + 24*arctan(1/12943) pi/4 = 88*arctan(1/172) + 51*arctan(1/239) + 32*arctan(1/682) + 44*arctan(1/5357) + 68*arctan(1/12943) pi/4 = 88*arctan(1/172) + 51*arctan(1/239) + 32*arctan(1/682) + 44*arctan(1/5357) + 68*arctan(1/12944) EOT func parse_eqn(equation) { static eqn_re = %r{ (^ \s* pi/4 \s* = \s* )? (?: \s* ( [-+] )? \s* (?: ( \d+ ) \s* \*)? \s* arctan\((.*?)\) )}x gather { for lhs,sign,mult,rat in (equation.findall(eqn_re)) { take([ [+1, -1][sign == '-'] * (mult ? Num(mult) : 1), Num(rat) ]) } } } func tanEval(coef, f) { return f if (coef == 1) return -tanEval(-coef, f) if (coef < 0) var ca = coef>>1 var cb = (coef - ca) var (a, b) = (tanEval(ca, f), tanEval(cb, f)) (a + b) / (1 - a*b) } func tans(xs) { var xslen = xs.len return tanEval(xs[0]...) if (xslen == 1) var (aa, bb) = xs.part(xslen>>1) var (a, b) = (tans(aa), tans(bb)) (a + b) / (1 - a*b) } var machins = equationtext.lines.map(parse_eqn) for machin,eqn in (machins ~Z equationtext.lines) { var ans = tans(machin) printf("%5s: %s\n", (ans == 1 ? 'OK' : 'ERROR'), eqn) }
Preserve the algorithm and functionality while converting the code from Java to Ruby.
import java.io.UnsupportedEncodingException; import java.util.Arrays; import java.util.Random; public class IsaacRandom extends Random { private static final long serialVersionUID = 1L; private final int[] randResult = new int[256]; private int valuesUsed; private final int[] mm = new int[256]; private int aa, bb, cc; public IsaacRandom() { super(0); init(null); } public IsaacRandom(int[] seed) { super(0); setSeed(seed); } public IsaacRandom(String seed) { super(0); setSeed(seed); } private void generateMoreResults() { cc++; bb += cc; for (int i=0; i<256; i++) { int x = mm[i]; switch (i&3) { case 0: aa = aa^(aa<<13); break; case 1: aa = aa^(aa>>>6); break; case 2: aa = aa^(aa<<2); break; case 3: aa = aa^(aa>>>16); break; } aa = mm[i^128] + aa; int y = mm[i] = mm[(x>>>2) & 0xFF] + aa + bb; randResult[i] = bb = mm[(y>>>10) & 0xFF] + x; } valuesUsed = 0; } private static void mix(int[] s) { s[0]^=s[1]<<11; s[3]+=s[0]; s[1]+=s[2]; s[1]^=s[2]>>>2; s[4]+=s[1]; s[2]+=s[3]; s[2]^=s[3]<<8; s[5]+=s[2]; s[3]+=s[4]; s[3]^=s[4]>>>16; s[6]+=s[3]; s[4]+=s[5]; s[4]^=s[5]<<10; s[7]+=s[4]; s[5]+=s[6]; s[5]^=s[6]>>>4; s[0]+=s[5]; s[6]+=s[7]; s[6]^=s[7]<<8; s[1]+=s[6]; s[7]+=s[0]; s[7]^=s[0]>>>9; s[2]+=s[7]; s[0]+=s[1]; } private void init(int[] seed) { if (seed != null && seed.length != 256) { seed = Arrays.copyOf(seed, 256); } aa = bb = cc = 0; int[] initState = new int[8]; Arrays.fill(initState, 0x9e3779b9); for (int i=0; i<4; i++) { mix(initState); } for (int i=0; i<256; i+=8) { if (seed != null) { for (int j=0; j<8; j++) { initState[j] += seed[i+j]; } } mix(initState); for (int j=0; j<8; j++) { mm[i+j] = initState[j]; } } if (seed != null) { for (int i=0; i<256; i+=8) { for (int j=0; j<8; j++) { initState[j] += mm[i+j]; } mix(initState); for (int j=0; j<8; j++) { mm[i+j] = initState[j]; } } } valuesUsed = 256; } @Override protected int next(int bits) { if (valuesUsed == 256) { generateMoreResults(); assert(valuesUsed == 0); } int value = randResult[valuesUsed]; valuesUsed++; return value >>> (32-bits); } @Override public synchronized void setSeed(long seed) { super.setSeed(0); if (mm == null) { return; } int[] arraySeed = new int[256]; arraySeed[0] = (int) (seed & 0xFFFFFFFF); arraySeed[1] = (int) (seed >>> 32); init(arraySeed); } public synchronized void setSeed(int[] seed) { super.setSeed(0); init(seed); } public synchronized void setSeed(String seed) { super.setSeed(0); char[] charSeed = seed.toCharArray(); int[] intSeed = new int[charSeed.length]; for (int i=0; i<charSeed.length; i++) { intSeed[i] = charSeed[i]; } init(intSeed); } public int randomChar() { long unsignedNext = nextInt() & 0xFFFFFFFFL; return (int) (unsignedNext % 95 + 32); } public enum CipherMode { ENCIPHER, DECIPHER, NONE }; public byte[] vernamCipher(byte[] input) { byte[] result = new byte[input.length]; for (int i=0; i<input.length; i++) { result[i] = (byte) (randomChar() ^ input[i]); } return result; } private static byte caesarShift(CipherMode mode, byte ch, int shift, byte modulo, byte start) { if (mode == CipherMode.DECIPHER) { shift = -shift; } int n = (ch-start) + shift; n %= modulo; if (n<0) { n += modulo; } return (byte) (start + n); } public byte[] caesarCipher(CipherMode mode, byte[] input, byte modulo, byte start) { byte[] result = new byte[input.length]; for (int i=0; i<input.length; i++) { result[i] = caesarShift(mode, input[i], randomChar(), modulo, start); } return result; } private static String toHexString(byte[] input) { StringBuilder sb = new StringBuilder(input.length*2); for (byte b : input) { sb.append(String.format("%02X", b)); } return sb.toString(); } public static void main(String[] args) { final byte MOD = 95; final byte START = 32; String secret = "a Top Secret secret"; String key = "this is my secret key"; IsaacRandom random = new IsaacRandom(key); byte[] vernamResult; byte[] caesarResult; String vernamDecrypted; String caesarDecrypted; try { vernamResult = random.vernamCipher(secret.getBytes("ASCII")); caesarResult = random.caesarCipher(CipherMode.ENCIPHER, secret.getBytes("ASCII"), MOD, START); random.setSeed(key); vernamDecrypted = new String(random.vernamCipher(vernamResult), "ASCII"); caesarDecrypted = new String(random.caesarCipher(CipherMode.DECIPHER, caesarResult, MOD, START), "ASCII"); } catch (UnsupportedEncodingException e) { throw new InternalError("JVM isn't conforming - ASCII encoding isn't available"); } System.out.printf("Message: %s\n", secret); System.out.printf("Key  : %s\n", key); System.out.printf("XOR  : %s\n", toHexString(vernamResult)); System.out.printf("XOR dcr: %s\n", vernamDecrypted); System.out.printf("MOD  : %s\n", toHexString(caesarResult)); System.out.printf("MOD dcr: %s\n", caesarDecrypted); } }
require('Math::Random::ISAAC') func xor_isaac(key, msg) { var rng = %O<Math::Random::ISAAC>.new(unpack('C*', key)) msg.chars»ord()» \ -> »^« 256.of{ rng.irand % 95 + 32 }.last(msg.len).flip \ -> «%« '%02X' -> join } var msg = 'a Top Secret secret' var key = 'this is my secret key' var enc = xor_isaac(key, msg) var dec = xor_isaac(key, pack('H*', enc)) say "Message: say "Key  : say "XOR  : say "XOR dcr:
Convert the following code from Java to Ruby, ensuring the logic remains intact.
import java.io.UnsupportedEncodingException; import java.util.Arrays; import java.util.Random; public class IsaacRandom extends Random { private static final long serialVersionUID = 1L; private final int[] randResult = new int[256]; private int valuesUsed; private final int[] mm = new int[256]; private int aa, bb, cc; public IsaacRandom() { super(0); init(null); } public IsaacRandom(int[] seed) { super(0); setSeed(seed); } public IsaacRandom(String seed) { super(0); setSeed(seed); } private void generateMoreResults() { cc++; bb += cc; for (int i=0; i<256; i++) { int x = mm[i]; switch (i&3) { case 0: aa = aa^(aa<<13); break; case 1: aa = aa^(aa>>>6); break; case 2: aa = aa^(aa<<2); break; case 3: aa = aa^(aa>>>16); break; } aa = mm[i^128] + aa; int y = mm[i] = mm[(x>>>2) & 0xFF] + aa + bb; randResult[i] = bb = mm[(y>>>10) & 0xFF] + x; } valuesUsed = 0; } private static void mix(int[] s) { s[0]^=s[1]<<11; s[3]+=s[0]; s[1]+=s[2]; s[1]^=s[2]>>>2; s[4]+=s[1]; s[2]+=s[3]; s[2]^=s[3]<<8; s[5]+=s[2]; s[3]+=s[4]; s[3]^=s[4]>>>16; s[6]+=s[3]; s[4]+=s[5]; s[4]^=s[5]<<10; s[7]+=s[4]; s[5]+=s[6]; s[5]^=s[6]>>>4; s[0]+=s[5]; s[6]+=s[7]; s[6]^=s[7]<<8; s[1]+=s[6]; s[7]+=s[0]; s[7]^=s[0]>>>9; s[2]+=s[7]; s[0]+=s[1]; } private void init(int[] seed) { if (seed != null && seed.length != 256) { seed = Arrays.copyOf(seed, 256); } aa = bb = cc = 0; int[] initState = new int[8]; Arrays.fill(initState, 0x9e3779b9); for (int i=0; i<4; i++) { mix(initState); } for (int i=0; i<256; i+=8) { if (seed != null) { for (int j=0; j<8; j++) { initState[j] += seed[i+j]; } } mix(initState); for (int j=0; j<8; j++) { mm[i+j] = initState[j]; } } if (seed != null) { for (int i=0; i<256; i+=8) { for (int j=0; j<8; j++) { initState[j] += mm[i+j]; } mix(initState); for (int j=0; j<8; j++) { mm[i+j] = initState[j]; } } } valuesUsed = 256; } @Override protected int next(int bits) { if (valuesUsed == 256) { generateMoreResults(); assert(valuesUsed == 0); } int value = randResult[valuesUsed]; valuesUsed++; return value >>> (32-bits); } @Override public synchronized void setSeed(long seed) { super.setSeed(0); if (mm == null) { return; } int[] arraySeed = new int[256]; arraySeed[0] = (int) (seed & 0xFFFFFFFF); arraySeed[1] = (int) (seed >>> 32); init(arraySeed); } public synchronized void setSeed(int[] seed) { super.setSeed(0); init(seed); } public synchronized void setSeed(String seed) { super.setSeed(0); char[] charSeed = seed.toCharArray(); int[] intSeed = new int[charSeed.length]; for (int i=0; i<charSeed.length; i++) { intSeed[i] = charSeed[i]; } init(intSeed); } public int randomChar() { long unsignedNext = nextInt() & 0xFFFFFFFFL; return (int) (unsignedNext % 95 + 32); } public enum CipherMode { ENCIPHER, DECIPHER, NONE }; public byte[] vernamCipher(byte[] input) { byte[] result = new byte[input.length]; for (int i=0; i<input.length; i++) { result[i] = (byte) (randomChar() ^ input[i]); } return result; } private static byte caesarShift(CipherMode mode, byte ch, int shift, byte modulo, byte start) { if (mode == CipherMode.DECIPHER) { shift = -shift; } int n = (ch-start) + shift; n %= modulo; if (n<0) { n += modulo; } return (byte) (start + n); } public byte[] caesarCipher(CipherMode mode, byte[] input, byte modulo, byte start) { byte[] result = new byte[input.length]; for (int i=0; i<input.length; i++) { result[i] = caesarShift(mode, input[i], randomChar(), modulo, start); } return result; } private static String toHexString(byte[] input) { StringBuilder sb = new StringBuilder(input.length*2); for (byte b : input) { sb.append(String.format("%02X", b)); } return sb.toString(); } public static void main(String[] args) { final byte MOD = 95; final byte START = 32; String secret = "a Top Secret secret"; String key = "this is my secret key"; IsaacRandom random = new IsaacRandom(key); byte[] vernamResult; byte[] caesarResult; String vernamDecrypted; String caesarDecrypted; try { vernamResult = random.vernamCipher(secret.getBytes("ASCII")); caesarResult = random.caesarCipher(CipherMode.ENCIPHER, secret.getBytes("ASCII"), MOD, START); random.setSeed(key); vernamDecrypted = new String(random.vernamCipher(vernamResult), "ASCII"); caesarDecrypted = new String(random.caesarCipher(CipherMode.DECIPHER, caesarResult, MOD, START), "ASCII"); } catch (UnsupportedEncodingException e) { throw new InternalError("JVM isn't conforming - ASCII encoding isn't available"); } System.out.printf("Message: %s\n", secret); System.out.printf("Key  : %s\n", key); System.out.printf("XOR  : %s\n", toHexString(vernamResult)); System.out.printf("XOR dcr: %s\n", vernamDecrypted); System.out.printf("MOD  : %s\n", toHexString(caesarResult)); System.out.printf("MOD dcr: %s\n", caesarDecrypted); } }
require('Math::Random::ISAAC') func xor_isaac(key, msg) { var rng = %O<Math::Random::ISAAC>.new(unpack('C*', key)) msg.chars»ord()» \ -> »^« 256.of{ rng.irand % 95 + 32 }.last(msg.len).flip \ -> «%« '%02X' -> join } var msg = 'a Top Secret secret' var key = 'this is my secret key' var enc = xor_isaac(key, msg) var dec = xor_isaac(key, pack('H*', enc)) say "Message: say "Key  : say "XOR  : say "XOR dcr:
Write the same algorithm in Ruby as shown in this Java implementation.
import java.math.BigInteger; import java.util.*; class RankPermutation { public static BigInteger getRank(int[] permutation) { int n = permutation.length; BitSet usedDigits = new BitSet(); BigInteger rank = BigInteger.ZERO; for (int i = 0; i < n; i++) { rank = rank.multiply(BigInteger.valueOf(n - i)); int digit = 0; int v = -1; while ((v = usedDigits.nextClearBit(v + 1)) < permutation[i]) digit++; usedDigits.set(v); rank = rank.add(BigInteger.valueOf(digit)); } return rank; } public static int[] getPermutation(int n, BigInteger rank) { int[] digits = new int[n]; for (int digit = 2; digit <= n; digit++) { BigInteger divisor = BigInteger.valueOf(digit); digits[n - digit] = rank.mod(divisor).intValue(); if (digit < n) rank = rank.divide(divisor); } BitSet usedDigits = new BitSet(); int[] permutation = new int[n]; for (int i = 0; i < n; i++) { int v = usedDigits.nextClearBit(0); for (int j = 0; j < digits[i]; j++) v = usedDigits.nextClearBit(v + 1); permutation[i] = v; usedDigits.set(v); } return permutation; } public static void main(String[] args) { for (int i = 0; i < 6; i++) { int[] permutation = getPermutation(3, BigInteger.valueOf(i)); System.out.println(String.valueOf(i) + " --> " + Arrays.toString(permutation) + " --> " + getRank(permutation)); } Random rnd = new Random(); for (int n : new int[] { 12, 144 }) { BigInteger factorial = BigInteger.ONE; for (int i = 2; i <= n; i++) factorial = factorial.multiply(BigInteger.valueOf(i)); System.out.println("n = " + n); for (int i = 0; i < 5; i++) { BigInteger rank = new BigInteger((factorial.bitLength() + 1) << 1, rnd); rank = rank.mod(factorial); int[] permutation = getPermutation(n, rank); System.out.println(" " + rank + " --> " + Arrays.toString(permutation) + " --> " + getRank(permutation)); } } } }
class Permutation include Enumerable attr_reader :num_elements, :size def initialize(num_elements) @num_elements = num_elements @size = fact(num_elements) end def each return self.to_enum unless block_given? (0...@size).each{|i| yield unrank(i)} end def unrank(r) pi = (0...num_elements).to_a (@num_elements-1).downto(1) do |n| s, r = r.divmod(fact(n)) pi[n], pi[s] = pi[s], pi[n] end pi end def rank(pi) pi = pi.dup pi1 = pi.zip(0...pi.size).sort.map(&:last) (pi.size-1).downto(0).inject(0) do |memo,i| pi[i], pi[pi1[i]] = pi[pi1[i]], (s = pi[i]) pi1[s], pi1[i] = pi1[i], pi1[s] memo += s * fact(i) end end private def fact(n) n.zero? ? 1 : n.downto(1).inject(:*) end end
Generate an equivalent Ruby version of this Java code.
import java.math.BigInteger; import java.util.*; class RankPermutation { public static BigInteger getRank(int[] permutation) { int n = permutation.length; BitSet usedDigits = new BitSet(); BigInteger rank = BigInteger.ZERO; for (int i = 0; i < n; i++) { rank = rank.multiply(BigInteger.valueOf(n - i)); int digit = 0; int v = -1; while ((v = usedDigits.nextClearBit(v + 1)) < permutation[i]) digit++; usedDigits.set(v); rank = rank.add(BigInteger.valueOf(digit)); } return rank; } public static int[] getPermutation(int n, BigInteger rank) { int[] digits = new int[n]; for (int digit = 2; digit <= n; digit++) { BigInteger divisor = BigInteger.valueOf(digit); digits[n - digit] = rank.mod(divisor).intValue(); if (digit < n) rank = rank.divide(divisor); } BitSet usedDigits = new BitSet(); int[] permutation = new int[n]; for (int i = 0; i < n; i++) { int v = usedDigits.nextClearBit(0); for (int j = 0; j < digits[i]; j++) v = usedDigits.nextClearBit(v + 1); permutation[i] = v; usedDigits.set(v); } return permutation; } public static void main(String[] args) { for (int i = 0; i < 6; i++) { int[] permutation = getPermutation(3, BigInteger.valueOf(i)); System.out.println(String.valueOf(i) + " --> " + Arrays.toString(permutation) + " --> " + getRank(permutation)); } Random rnd = new Random(); for (int n : new int[] { 12, 144 }) { BigInteger factorial = BigInteger.ONE; for (int i = 2; i <= n; i++) factorial = factorial.multiply(BigInteger.valueOf(i)); System.out.println("n = " + n); for (int i = 0; i < 5; i++) { BigInteger rank = new BigInteger((factorial.bitLength() + 1) << 1, rnd); rank = rank.mod(factorial); int[] permutation = getPermutation(n, rank); System.out.println(" " + rank + " --> " + Arrays.toString(permutation) + " --> " + getRank(permutation)); } } } }
class Permutation include Enumerable attr_reader :num_elements, :size def initialize(num_elements) @num_elements = num_elements @size = fact(num_elements) end def each return self.to_enum unless block_given? (0...@size).each{|i| yield unrank(i)} end def unrank(r) pi = (0...num_elements).to_a (@num_elements-1).downto(1) do |n| s, r = r.divmod(fact(n)) pi[n], pi[s] = pi[s], pi[n] end pi end def rank(pi) pi = pi.dup pi1 = pi.zip(0...pi.size).sort.map(&:last) (pi.size-1).downto(0).inject(0) do |memo,i| pi[i], pi[pi1[i]] = pi[pi1[i]], (s = pi[i]) pi1[s], pi1[i] = pi1[i], pi1[s] memo += s * fact(i) end end private def fact(n) n.zero? ? 1 : n.downto(1).inject(:*) end end
Preserve the algorithm and functionality while converting the code from Java to Ruby.
public class FirstPowerOfTwo { public static void main(String[] args) { runTest(12, 1); runTest(12, 2); runTest(123, 45); runTest(123, 12345); runTest(123, 678910); } private static void runTest(int l, int n) { System.out.printf("p(%d, %d) = %,d%n", l, n, p(l, n)); } public static int p(int l, int n) { int test = 0; double log = Math.log(2) / Math.log(10); int factor = 1; int loop = l; while ( loop > 10 ) { factor *= 10; loop /= 10; } while ( n > 0) { test++; int val = (int) (factor * Math.pow(10, test * log % 1)); if ( val == l ) { n--; } } return test; } }
def p(l, n) test = 0 logv = Math.log(2.0) / Math.log(10.0) factor = 1 loopv = l while loopv > 10 do factor = factor * 10 loopv = loopv / 10 end while n > 0 do test = test + 1 val = (factor * (10.0 ** ((test * logv).modulo(1.0)))).floor if val == l then n = n - 1 end end return test end def runTest(l, n) print "P(%d, %d) = %d\n" % [l, n, p(l, n)] end runTest(12, 1) runTest(12, 2) runTest(123, 45) runTest(123, 12345) runTest(123, 678910)
Transform the following Java implementation into Ruby, maintaining the same output and logic.
public class FirstPowerOfTwo { public static void main(String[] args) { runTest(12, 1); runTest(12, 2); runTest(123, 45); runTest(123, 12345); runTest(123, 678910); } private static void runTest(int l, int n) { System.out.printf("p(%d, %d) = %,d%n", l, n, p(l, n)); } public static int p(int l, int n) { int test = 0; double log = Math.log(2) / Math.log(10); int factor = 1; int loop = l; while ( loop > 10 ) { factor *= 10; loop /= 10; } while ( n > 0) { test++; int val = (int) (factor * Math.pow(10, test * log % 1)); if ( val == l ) { n--; } } return test; } }
def p(l, n) test = 0 logv = Math.log(2.0) / Math.log(10.0) factor = 1 loopv = l while loopv > 10 do factor = factor * 10 loopv = loopv / 10 end while n > 0 do test = test + 1 val = (factor * (10.0 ** ((test * logv).modulo(1.0)))).floor if val == l then n = n - 1 end end return test end def runTest(l, n) print "P(%d, %d) = %d\n" % [l, n, p(l, n)] end runTest(12, 1) runTest(12, 2) runTest(123, 45) runTest(123, 12345) runTest(123, 678910)
Write the same code in Ruby as shown below in Java.
import java.math.BigInteger; import java.util.HashMap; import java.util.Map; public class SterlingNumbersSecondKind { public static void main(String[] args) { System.out.println("Stirling numbers of the second kind:"); int max = 12; System.out.printf("n/k"); for ( int n = 0 ; n <= max ; n++ ) { System.out.printf("%10d", n); } System.out.printf("%n"); for ( int n = 0 ; n <= max ; n++ ) { System.out.printf("%-3d", n); for ( int k = 0 ; k <= n ; k++ ) { System.out.printf("%10s", sterling2(n, k)); } System.out.printf("%n"); } System.out.println("The maximum value of S2(100, k) = "); BigInteger previous = BigInteger.ZERO; for ( int k = 1 ; k <= 100 ; k++ ) { BigInteger current = sterling2(100, k); if ( current.compareTo(previous) > 0 ) { previous = current; } else { System.out.printf("%s%n(%d digits, k = %d)%n", previous, previous.toString().length(), k-1); break; } } } private static Map<String,BigInteger> COMPUTED = new HashMap<>(); private static final BigInteger sterling2(int n, int k) { String key = n + "," + k; if ( COMPUTED.containsKey(key) ) { return COMPUTED.get(key); } if ( n == 0 && k == 0 ) { return BigInteger.valueOf(1); } if ( (n > 0 && k == 0) || (n == 0 && k > 0) ) { return BigInteger.ZERO; } if ( n == k ) { return BigInteger.valueOf(1); } if ( k > n ) { return BigInteger.ZERO; } BigInteger result = BigInteger.valueOf(k).multiply(sterling2(n-1, k)).add(sterling2(n-1, k-1)); COMPUTED.put(key, result); return result; } }
@memo = {} def sterling2(n, k) key = [n,k] return @memo[key] if @memo.key?(key) return 1 if n.zero? and k.zero? return 0 if n.zero? or k.zero? return 1 if n == k return 0 if k > n res = k * sterling2(n-1, k) + sterling2(n - 1, k-1) @memo[key] = res end r = (0..12) puts "Sterling2 numbers:" puts "n/k r.each do |row| print "%-4s" % row puts " end puts "\nMaximum value from the sterling2(100, k)"; puts (1..100).map{|a| sterling2(100,a)}.max
Convert this Java snippet to Ruby and keep its semantics consistent.
import java.math.BigInteger; import java.util.HashMap; import java.util.Map; public class SterlingNumbersSecondKind { public static void main(String[] args) { System.out.println("Stirling numbers of the second kind:"); int max = 12; System.out.printf("n/k"); for ( int n = 0 ; n <= max ; n++ ) { System.out.printf("%10d", n); } System.out.printf("%n"); for ( int n = 0 ; n <= max ; n++ ) { System.out.printf("%-3d", n); for ( int k = 0 ; k <= n ; k++ ) { System.out.printf("%10s", sterling2(n, k)); } System.out.printf("%n"); } System.out.println("The maximum value of S2(100, k) = "); BigInteger previous = BigInteger.ZERO; for ( int k = 1 ; k <= 100 ; k++ ) { BigInteger current = sterling2(100, k); if ( current.compareTo(previous) > 0 ) { previous = current; } else { System.out.printf("%s%n(%d digits, k = %d)%n", previous, previous.toString().length(), k-1); break; } } } private static Map<String,BigInteger> COMPUTED = new HashMap<>(); private static final BigInteger sterling2(int n, int k) { String key = n + "," + k; if ( COMPUTED.containsKey(key) ) { return COMPUTED.get(key); } if ( n == 0 && k == 0 ) { return BigInteger.valueOf(1); } if ( (n > 0 && k == 0) || (n == 0 && k > 0) ) { return BigInteger.ZERO; } if ( n == k ) { return BigInteger.valueOf(1); } if ( k > n ) { return BigInteger.ZERO; } BigInteger result = BigInteger.valueOf(k).multiply(sterling2(n-1, k)).add(sterling2(n-1, k-1)); COMPUTED.put(key, result); return result; } }
@memo = {} def sterling2(n, k) key = [n,k] return @memo[key] if @memo.key?(key) return 1 if n.zero? and k.zero? return 0 if n.zero? or k.zero? return 1 if n == k return 0 if k > n res = k * sterling2(n-1, k) + sterling2(n - 1, k-1) @memo[key] = res end r = (0..12) puts "Sterling2 numbers:" puts "n/k r.each do |row| print "%-4s" % row puts " end puts "\nMaximum value from the sterling2(100, k)"; puts (1..100).map{|a| sterling2(100,a)}.max
Convert this Java block to Ruby, preserving its control flow and logic.
import java.math.BigInteger; import java.util.function.BiFunction; import java.util.function.Function; public class CipollasAlgorithm { private static final BigInteger BIG = BigInteger.TEN.pow(50).add(BigInteger.valueOf(151)); private static final BigInteger BIG_TWO = BigInteger.valueOf(2); private static class Point { BigInteger x; BigInteger y; Point(BigInteger x, BigInteger y) { this.x = x; this.y = y; } @Override public String toString() { return String.format("(%s, %s)", this.x, this.y); } } private static class Triple { BigInteger x; BigInteger y; boolean b; Triple(BigInteger x, BigInteger y, boolean b) { this.x = x; this.y = y; this.b = b; } @Override public String toString() { return String.format("(%s, %s, %s)", this.x, this.y, this.b); } } private static Triple c(String ns, String ps) { BigInteger n = new BigInteger(ns); BigInteger p = !ps.isEmpty() ? new BigInteger(ps) : BIG; Function<BigInteger, BigInteger> ls = (BigInteger a) -> a.modPow(p.subtract(BigInteger.ONE).divide(BIG_TWO), p); if (!ls.apply(n).equals(BigInteger.ONE)) { return new Triple(BigInteger.ZERO, BigInteger.ZERO, false); } BigInteger a = BigInteger.ZERO; BigInteger omega2; while (true) { omega2 = a.multiply(a).add(p).subtract(n).mod(p); if (ls.apply(omega2).equals(p.subtract(BigInteger.ONE))) { break; } a = a.add(BigInteger.ONE); } BigInteger finalOmega = omega2; BiFunction<Point, Point, Point> mul = (Point aa, Point bb) -> new Point( aa.x.multiply(bb.x).add(aa.y.multiply(bb.y).multiply(finalOmega)).mod(p), aa.x.multiply(bb.y).add(bb.x.multiply(aa.y)).mod(p) ); Point r = new Point(BigInteger.ONE, BigInteger.ZERO); Point s = new Point(a, BigInteger.ONE); BigInteger nn = p.add(BigInteger.ONE).shiftRight(1).mod(p); while (nn.compareTo(BigInteger.ZERO) > 0) { if (nn.and(BigInteger.ONE).equals(BigInteger.ONE)) { r = mul.apply(r, s); } s = mul.apply(s, s); nn = nn.shiftRight(1); } if (!r.y.equals(BigInteger.ZERO)) { return new Triple(BigInteger.ZERO, BigInteger.ZERO, false); } if (!r.x.multiply(r.x).mod(p).equals(n)) { return new Triple(BigInteger.ZERO, BigInteger.ZERO, false); } return new Triple(r.x, p.subtract(r.x), true); } public static void main(String[] args) { System.out.println(c("10", "13")); System.out.println(c("56", "101")); System.out.println(c("8218", "10007")); System.out.println(c("8219", "10007")); System.out.println(c("331575", "1000003")); System.out.println(c("665165880", "1000000007")); System.out.println(c("881398088036", "1000000000039")); System.out.println(c("34035243914635549601583369544560650254325084643201", "")); } }
func cipolla(n, p) { legendre(n, p) == 1 || return nil var (a = 0, ω2 = 0) loop { ω2 = ((a*a - n) % p) if (legendre(ω2, p) == -1) { break } ++a } struct point { x, y } func mul(a, b) { point((a.x*b.x + a.y*b.y*ω2) % p, (a.x*b.y + b.x*a.y) % p) } var r = point(1, 0) var s = point(a, 1) for (var n = ((p+1) >> 1); n > 0; n >>= 1) { r = mul(r, s) if n.is_odd s = mul(s, s) } r.y == 0 ? r.x : nil } var tests = [ [10, 13], [56, 101], [8218, 10007], [8219, 10007], [331575, 1000003], [665165880, 1000000007], [881398088036 1000000000039], [34035243914635549601583369544560650254325084643201, 10**50 + 151], ] for n,p in tests { var r = cipolla(n, p) if (defined(r)) { say "Roots of } else { say "No solution for ( } }
Write the same code in Ruby as shown below in Java.
import java.math.BigInteger; import java.util.function.BiFunction; import java.util.function.Function; public class CipollasAlgorithm { private static final BigInteger BIG = BigInteger.TEN.pow(50).add(BigInteger.valueOf(151)); private static final BigInteger BIG_TWO = BigInteger.valueOf(2); private static class Point { BigInteger x; BigInteger y; Point(BigInteger x, BigInteger y) { this.x = x; this.y = y; } @Override public String toString() { return String.format("(%s, %s)", this.x, this.y); } } private static class Triple { BigInteger x; BigInteger y; boolean b; Triple(BigInteger x, BigInteger y, boolean b) { this.x = x; this.y = y; this.b = b; } @Override public String toString() { return String.format("(%s, %s, %s)", this.x, this.y, this.b); } } private static Triple c(String ns, String ps) { BigInteger n = new BigInteger(ns); BigInteger p = !ps.isEmpty() ? new BigInteger(ps) : BIG; Function<BigInteger, BigInteger> ls = (BigInteger a) -> a.modPow(p.subtract(BigInteger.ONE).divide(BIG_TWO), p); if (!ls.apply(n).equals(BigInteger.ONE)) { return new Triple(BigInteger.ZERO, BigInteger.ZERO, false); } BigInteger a = BigInteger.ZERO; BigInteger omega2; while (true) { omega2 = a.multiply(a).add(p).subtract(n).mod(p); if (ls.apply(omega2).equals(p.subtract(BigInteger.ONE))) { break; } a = a.add(BigInteger.ONE); } BigInteger finalOmega = omega2; BiFunction<Point, Point, Point> mul = (Point aa, Point bb) -> new Point( aa.x.multiply(bb.x).add(aa.y.multiply(bb.y).multiply(finalOmega)).mod(p), aa.x.multiply(bb.y).add(bb.x.multiply(aa.y)).mod(p) ); Point r = new Point(BigInteger.ONE, BigInteger.ZERO); Point s = new Point(a, BigInteger.ONE); BigInteger nn = p.add(BigInteger.ONE).shiftRight(1).mod(p); while (nn.compareTo(BigInteger.ZERO) > 0) { if (nn.and(BigInteger.ONE).equals(BigInteger.ONE)) { r = mul.apply(r, s); } s = mul.apply(s, s); nn = nn.shiftRight(1); } if (!r.y.equals(BigInteger.ZERO)) { return new Triple(BigInteger.ZERO, BigInteger.ZERO, false); } if (!r.x.multiply(r.x).mod(p).equals(n)) { return new Triple(BigInteger.ZERO, BigInteger.ZERO, false); } return new Triple(r.x, p.subtract(r.x), true); } public static void main(String[] args) { System.out.println(c("10", "13")); System.out.println(c("56", "101")); System.out.println(c("8218", "10007")); System.out.println(c("8219", "10007")); System.out.println(c("331575", "1000003")); System.out.println(c("665165880", "1000000007")); System.out.println(c("881398088036", "1000000000039")); System.out.println(c("34035243914635549601583369544560650254325084643201", "")); } }
func cipolla(n, p) { legendre(n, p) == 1 || return nil var (a = 0, ω2 = 0) loop { ω2 = ((a*a - n) % p) if (legendre(ω2, p) == -1) { break } ++a } struct point { x, y } func mul(a, b) { point((a.x*b.x + a.y*b.y*ω2) % p, (a.x*b.y + b.x*a.y) % p) } var r = point(1, 0) var s = point(a, 1) for (var n = ((p+1) >> 1); n > 0; n >>= 1) { r = mul(r, s) if n.is_odd s = mul(s, s) } r.y == 0 ? r.x : nil } var tests = [ [10, 13], [56, 101], [8218, 10007], [8219, 10007], [331575, 1000003], [665165880, 1000000007], [881398088036 1000000000039], [34035243914635549601583369544560650254325084643201, 10**50 + 151], ] for n,p in tests { var r = cipolla(n, p) if (defined(r)) { say "Roots of } else { say "No solution for ( } }
Port the following code from Java to Ruby with equivalent syntax and logic.
import java.math.BigInteger; import java.text.NumberFormat; import java.util.ArrayList; import java.util.List; public class PierpontPrimes { public static void main(String[] args) { NumberFormat nf = NumberFormat.getNumberInstance(); display("First 50 Pierpont primes of the first kind:", pierpontPrimes(50, true)); display("First 50 Pierpont primes of the second kind:", pierpontPrimes(50, false)); System.out.printf("250th Pierpont prime of the first kind: %s%n%n", nf.format(pierpontPrimes(250, true).get(249))); System.out.printf("250th Pierpont prime of the second kind: %s%n%n", nf.format(pierpontPrimes(250, false).get(249))); } private static void display(String message, List<BigInteger> primes) { NumberFormat nf = NumberFormat.getNumberInstance(); System.out.printf("%s%n", message); for ( int i = 1 ; i <= primes.size() ; i++ ) { System.out.printf("%10s ", nf.format(primes.get(i-1))); if ( i % 10 == 0 ) { System.out.printf("%n"); } } System.out.printf("%n"); } public static List<BigInteger> pierpontPrimes(int n, boolean first) { List<BigInteger> primes = new ArrayList<BigInteger>(); if ( first ) { primes.add(BigInteger.valueOf(2)); n -= 1; } BigInteger two = BigInteger.valueOf(2); BigInteger twoTest = two; BigInteger three = BigInteger.valueOf(3); BigInteger threeTest = three; int twoIndex = 0, threeIndex = 0; List<BigInteger> twoSmooth = new ArrayList<BigInteger>(); BigInteger one = BigInteger.ONE; BigInteger mOne = BigInteger.valueOf(-1); int count = 0; while ( count < n ) { BigInteger min = twoTest.min(threeTest); twoSmooth.add(min); if ( min.compareTo(twoTest) == 0 ) { twoTest = two.multiply(twoSmooth.get(twoIndex)); twoIndex++; } if ( min.compareTo(threeTest) == 0 ) { threeTest = three.multiply(twoSmooth.get(threeIndex)); threeIndex++; } BigInteger test = min.add(first ? one : mOne); if ( test.isProbablePrime(10) ) { primes.add(test); count++; } } return primes; } }
require 'gmp' def smooth_generator(ar) return to_enum(__method__, ar) unless block_given? next_smooth = 1 queues = ar.map{|num| [num, []] } loop do yield next_smooth queues.each {|m, queue| queue << next_smooth * m} next_smooth = queues.collect{|m, queue| queue.first}.min queues.each{|m, queue| queue.shift if queue.first == next_smooth } end end def pierpont(num = 1) return to_enum(__method__, num) unless block_given? smooth_generator([2,3]).each{|smooth| yield smooth+num if GMP::Z(smooth + num).probab_prime? > 0} end def puts_cols(ar, n=10) ar.each_slice(n).map{|slice|puts slice.map{|n| n.to_s.rjust(10)}.join } end n, m = 50, 250 puts "First puts_cols(pierpont.take(n)) puts " puts "First puts_cols(pierpont(-1).take(n)) puts "
Write a version of this Java function in Ruby with identical behavior.
import java.math.BigInteger; import java.util.ArrayList; import java.util.List; public class NSmoothNumbers { public static void main(String[] args) { System.out.printf("show the first 25 n-smooth numbers for n = 2 through n = 29%n"); int max = 25; List<BigInteger> primes = new ArrayList<>(); for ( int n = 2 ; n <= 29 ; n++ ) { if ( isPrime(n) ) { primes.add(BigInteger.valueOf(n)); System.out.printf("The first %d %d-smooth numbers:%n", max, n); BigInteger[] humble = nSmooth(max, primes.toArray(new BigInteger[0])); for ( int i = 0 ; i < max ; i++ ) { System.out.printf("%s ", humble[i]); } System.out.printf("%n%n"); } } System.out.printf("show three numbers starting with 3,000 for n-smooth numbers for n = 3 through n = 29%n"); int count = 3; max = 3000 + count - 1; primes = new ArrayList<>(); primes.add(BigInteger.valueOf(2)); for ( int n = 3 ; n <= 29 ; n++ ) { if ( isPrime(n) ) { primes.add(BigInteger.valueOf(n)); System.out.printf("The %d through %d %d-smooth numbers:%n", max-count+1, max, n); BigInteger[] nSmooth = nSmooth(max, primes.toArray(new BigInteger[0])); for ( int i = max-count ; i < max ; i++ ) { System.out.printf("%s ", nSmooth[i]); } System.out.printf("%n%n"); } } System.out.printf("Show twenty numbers starting with 30,000 n-smooth numbers for n=503 through n=521%n"); count = 20; max = 30000 + count - 1; primes = new ArrayList<>(); for ( int n = 2 ; n <= 521 ; n++ ) { if ( isPrime(n) ) { primes.add(BigInteger.valueOf(n)); if ( n >= 503 && n <= 521 ) { System.out.printf("The %d through %d %d-smooth numbers:%n", max-count+1, max, n); BigInteger[] nSmooth = nSmooth(max, primes.toArray(new BigInteger[0])); for ( int i = max-count ; i < max ; i++ ) { System.out.printf("%s ", nSmooth[i]); } System.out.printf("%n%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 BigInteger[] nSmooth(int n, BigInteger[] primes) { int size = primes.length; BigInteger[] test = new BigInteger[size]; for ( int i = 0 ; i < size ; i++ ) { test[i] = primes[i]; } BigInteger[] results = new BigInteger[n]; results[0] = BigInteger.ONE; int[] indexes = new int[size]; for ( int i = 0 ; i < size ; i++ ) { indexes[i] = 0; } for ( int index = 1 ; index < n ; index++ ) { BigInteger min = test[0]; for ( int i = 1 ; i < size ; i++ ) { min = min.min(test[i]); } results[index] = min; for ( int i = 0 ; i < size ; i++ ) { if ( results[index].compareTo(test[i]) == 0 ) { indexes[i] = indexes[i] + 1; test[i] = primes[i].multiply(results[indexes[i]]); } } } return results; } }
require "big" def prime?(n) return false unless (n | 1 == 3 if n < 5) || (n % 6) | 4 == 5 sqrt_n = Math.isqrt(n) pc = typeof(n).new(5) while pc <= sqrt_n return false if n % pc == 0 || n % (pc + 2) == 0 pc += 6 end true end def gen_primes(a, b) (a..b).select { |pc| pc if prime? pc } end def nsmooth(n, limit) raise "Exception(n or limit)" if n < 2 || n > 521 || limit < 1 raise "Exception(must be a prime number: n)" unless prime? n primes = gen_primes(2, n) ns = [0.to_big_i] * limit ns[0] = 1.to_big_i nextp = primes[0..primes.index(n)].map { |prm| prm.to_big_i } indices = [0] * nextp.size (1...limit).each do |m| ns[m] = nextp.min (0...indices.size).each do |i| if ns[m] == nextp[i] indices[i] += 1 nextp[i] = primes[i] * ns[indices[i]] end end end ns end gen_primes(2, 29).each do |prime| print "The first 25 print nsmooth(prime, 25) puts end puts gen_primes(3, 29).each do |prime| print "The 3000 to 3202 print nsmooth(prime, 3002)[2999..] puts end puts gen_primes(503, 521).each do |prime| print "The 30,000 to 30,019 print nsmooth(prime, 30019)[29999..] puts end
Maintain the same structure and functionality when rewriting this code in Ruby.
import java.util.Arrays; import java.util.stream.IntStream; public class PartitionInteger { private static final int[] primes = IntStream.concat(IntStream.of(2), IntStream.iterate(3, n -> n + 2)) .filter(PartitionInteger::isPrime) .limit(50_000) .toArray(); 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; int d = 5; while (d * d <= n) { if (n % d == 0) return false; d += 2; if (n % d == 0) return false; d += 4; } return true; } private static boolean findCombo(int k, int x, int m, int n, int[] combo) { boolean foundCombo = false; if (k >= m) { if (Arrays.stream(combo).map(i -> primes[i]).sum() == x) { String s = m > 1 ? "s" : ""; System.out.printf("Partitioned %5d with %2d prime%s: ", x, m, s); for (int i = 0; i < m; ++i) { System.out.print(primes[combo[i]]); if (i < m - 1) System.out.print('+'); else System.out.println(); } foundCombo = true; } } else { for (int j = 0; j < n; ++j) { if (k == 0 || j > combo[k - 1]) { combo[k] = j; if (!foundCombo) { foundCombo = findCombo(k + 1, x, m, n, combo); } } } } return foundCombo; } private static void partition(int x, int m) { if (x < 2 || m < 1 || m >= x) { throw new IllegalArgumentException(); } int[] filteredPrimes = Arrays.stream(primes).filter(it -> it <= x).toArray(); int n = filteredPrimes.length; if (n < m) throw new IllegalArgumentException("Not enough primes"); int[] combo = new int[m]; boolean foundCombo = findCombo(0, x, m, n, combo); if (!foundCombo) { String s = m > 1 ? "s" : " "; System.out.printf("Partitioned %5d with %2d prime%s: (not possible)\n", x, m, s); } } public static void main(String[] args) { partition(99809, 1); partition(18, 2); partition(19, 3); partition(20, 4); partition(2017, 24); partition(22699, 1); partition(22699, 2); partition(22699, 3); partition(22699, 4); partition(40355, 3); } }
require "prime" def prime_partition(x, n) Prime.each(x).to_a.combination(n).detect{|primes| primes.sum == x} end TESTCASES = [[99809, 1], [18, 2], [19, 3], [20, 4], [2017, 24], [22699, 1], [22699, 2], [22699, 3], [22699, 4], [40355, 3]] TESTCASES.each do |prime, num| res = prime_partition(prime, num) str = res.nil? ? "no solution" : res.join(" + ") puts "Partitioned end
Please provide an equivalent version of this Java code in Ruby.
import java.math.BigInteger; import java.util.HashMap; import java.util.Map; public class SterlingNumbersFirstKind { public static void main(String[] args) { System.out.println("Unsigned Stirling numbers of the first kind:"); int max = 12; System.out.printf("n/k"); for ( int n = 0 ; n <= max ; n++ ) { System.out.printf("%10d", n); } System.out.printf("%n"); for ( int n = 0 ; n <= max ; n++ ) { System.out.printf("%-3d", n); for ( int k = 0 ; k <= n ; k++ ) { System.out.printf("%10s", sterling1(n, k)); } System.out.printf("%n"); } System.out.println("The maximum value of S1(100, k) = "); BigInteger previous = BigInteger.ZERO; for ( int k = 1 ; k <= 100 ; k++ ) { BigInteger current = sterling1(100, k); if ( current.compareTo(previous) > 0 ) { previous = current; } else { System.out.printf("%s%n(%d digits, k = %d)%n", previous, previous.toString().length(), k-1); break; } } } private static Map<String,BigInteger> COMPUTED = new HashMap<>(); private static final BigInteger sterling1(int n, int k) { String key = n + "," + k; if ( COMPUTED.containsKey(key) ) { return COMPUTED.get(key); } if ( n == 0 && k == 0 ) { return BigInteger.valueOf(1); } if ( n > 0 && k == 0 ) { return BigInteger.ZERO; } if ( k > n ) { return BigInteger.ZERO; } BigInteger result = sterling1(n-1, k-1).add(BigInteger.valueOf(n-1).multiply(sterling1(n-1, k))); COMPUTED.put(key, result); return result; } }
$cache = {} def sterling1(n, k) if n == 0 and k == 0 then return 1 end if n > 0 and k == 0 then return 0 end if k > n then return 0 end key = [n, k] if $cache[key] then return $cache[key] end value = sterling1(n - 1, k - 1) + (n - 1) * sterling1(n - 1, k) $cache[key] = value return value end MAX = 12 def main print "Unsigned Stirling numbers of the first kind:\n" print "n/k" for n in 0 .. MAX print "%10d" % [n] end print "\n" for n in 0 .. MAX print "%-3d" % [n] for k in 0 .. n print "%10d" % [sterling1(n, k)] end print "\n" end print "The maximum value of S1(100, k) =\n" previous = 0 for k in 1 .. 100 current = sterling1(100, k) if previous < current then previous = current else print previous, "\n" print "(%d digits, k = %d)\n" % [previous.to_s.length, k - 1] break end end end main()
Produce a functionally identical Ruby code for the snippet given in Java.
import java.math.BigInteger; import java.util.HashMap; import java.util.Map; public class SterlingNumbersFirstKind { public static void main(String[] args) { System.out.println("Unsigned Stirling numbers of the first kind:"); int max = 12; System.out.printf("n/k"); for ( int n = 0 ; n <= max ; n++ ) { System.out.printf("%10d", n); } System.out.printf("%n"); for ( int n = 0 ; n <= max ; n++ ) { System.out.printf("%-3d", n); for ( int k = 0 ; k <= n ; k++ ) { System.out.printf("%10s", sterling1(n, k)); } System.out.printf("%n"); } System.out.println("The maximum value of S1(100, k) = "); BigInteger previous = BigInteger.ZERO; for ( int k = 1 ; k <= 100 ; k++ ) { BigInteger current = sterling1(100, k); if ( current.compareTo(previous) > 0 ) { previous = current; } else { System.out.printf("%s%n(%d digits, k = %d)%n", previous, previous.toString().length(), k-1); break; } } } private static Map<String,BigInteger> COMPUTED = new HashMap<>(); private static final BigInteger sterling1(int n, int k) { String key = n + "," + k; if ( COMPUTED.containsKey(key) ) { return COMPUTED.get(key); } if ( n == 0 && k == 0 ) { return BigInteger.valueOf(1); } if ( n > 0 && k == 0 ) { return BigInteger.ZERO; } if ( k > n ) { return BigInteger.ZERO; } BigInteger result = sterling1(n-1, k-1).add(BigInteger.valueOf(n-1).multiply(sterling1(n-1, k))); COMPUTED.put(key, result); return result; } }
$cache = {} def sterling1(n, k) if n == 0 and k == 0 then return 1 end if n > 0 and k == 0 then return 0 end if k > n then return 0 end key = [n, k] if $cache[key] then return $cache[key] end value = sterling1(n - 1, k - 1) + (n - 1) * sterling1(n - 1, k) $cache[key] = value return value end MAX = 12 def main print "Unsigned Stirling numbers of the first kind:\n" print "n/k" for n in 0 .. MAX print "%10d" % [n] end print "\n" for n in 0 .. MAX print "%-3d" % [n] for k in 0 .. n print "%10d" % [sterling1(n, k)] end print "\n" end print "The maximum value of S1(100, k) =\n" previous = 0 for k in 1 .. 100 current = sterling1(100, k) if previous < current then previous = current else print previous, "\n" print "(%d digits, k = %d)\n" % [previous.to_s.length, k - 1] break end end end main()
Maintain the same structure and functionality when rewriting this code in Ruby.
import javafx.util.Pair; import java.util.ArrayList; import java.util.List; public class LineSimplification { private static class Point extends Pair<Double, Double> { Point(Double key, Double value) { super(key, value); } @Override public String toString() { return String.format("(%f, %f)", getKey(), getValue()); } } private static double perpendicularDistance(Point pt, Point lineStart, Point lineEnd) { double dx = lineEnd.getKey() - lineStart.getKey(); double dy = lineEnd.getValue() - lineStart.getValue(); double mag = Math.hypot(dx, dy); if (mag > 0.0) { dx /= mag; dy /= mag; } double pvx = pt.getKey() - lineStart.getKey(); double pvy = pt.getValue() - lineStart.getValue(); double pvdot = dx * pvx + dy * pvy; double ax = pvx - pvdot * dx; double ay = pvy - pvdot * dy; return Math.hypot(ax, ay); } private static void ramerDouglasPeucker(List<Point> pointList, double epsilon, List<Point> out) { if (pointList.size() < 2) throw new IllegalArgumentException("Not enough points to simplify"); double dmax = 0.0; int index = 0; int end = pointList.size() - 1; for (int i = 1; i < end; ++i) { double d = perpendicularDistance(pointList.get(i), pointList.get(0), pointList.get(end)); if (d > dmax) { index = i; dmax = d; } } if (dmax > epsilon) { List<Point> recResults1 = new ArrayList<>(); List<Point> recResults2 = new ArrayList<>(); List<Point> firstLine = pointList.subList(0, index + 1); List<Point> lastLine = pointList.subList(index, pointList.size()); ramerDouglasPeucker(firstLine, epsilon, recResults1); ramerDouglasPeucker(lastLine, epsilon, recResults2); out.addAll(recResults1.subList(0, recResults1.size() - 1)); out.addAll(recResults2); if (out.size() < 2) throw new RuntimeException("Problem assembling output"); } else { out.clear(); out.add(pointList.get(0)); out.add(pointList.get(pointList.size() - 1)); } } public static void main(String[] args) { List<Point> pointList = List.of( new Point(0.0, 0.0), new Point(1.0, 0.1), new Point(2.0, -0.1), new Point(3.0, 5.0), new Point(4.0, 6.0), new Point(5.0, 7.0), new Point(6.0, 8.1), new Point(7.0, 9.0), new Point(8.0, 9.0), new Point(9.0, 9.0) ); List<Point> pointListOut = new ArrayList<>(); ramerDouglasPeucker(pointList, 1.0, pointListOut); System.out.println("Points remaining after simplification:"); pointListOut.forEach(System.out::println); } }
func perpendicular_distance(Arr start, Arr end, Arr point) { ((point == start) || (point == end)) && return 0 var (Δx, Δy ) = ( end »-« start)... var (Δpx, Δpy) = (point »-« start)... var h = hypot(Δx, Δy) [\Δx, \Δy].map { *_ /= h } (([Δpx, Δpy] »-« ([Δx, Δy] »*» (Δx*Δpx + Δy*Δpy))) »**» 2).sum.sqrt } func Ramer_Douglas_Peucker(Arr points { .all { .len > 1 } }, ε = 1) { points.len == 2 && return points var d = (^points -> map { perpendicular_distance(points[0], points[-1], points[_]) }) if (d.max > ε) { var i = d.index(d.max) return [Ramer_Douglas_Peucker(points.ft(0, i), ε).ft(0, -2)..., Ramer_Douglas_Peucker(points.ft(i), ε)...] } return [points[0,-1]] } say Ramer_Douglas_Peucker( [[0,0],[1,0.1],[2,-0.1],[3,5],[4,6],[5,7],[6,8.1],[7,9],[8,9],[9,9]] )
Write a version of this Java function in Ruby with identical behavior.
import javafx.util.Pair; import java.util.ArrayList; import java.util.List; public class LineSimplification { private static class Point extends Pair<Double, Double> { Point(Double key, Double value) { super(key, value); } @Override public String toString() { return String.format("(%f, %f)", getKey(), getValue()); } } private static double perpendicularDistance(Point pt, Point lineStart, Point lineEnd) { double dx = lineEnd.getKey() - lineStart.getKey(); double dy = lineEnd.getValue() - lineStart.getValue(); double mag = Math.hypot(dx, dy); if (mag > 0.0) { dx /= mag; dy /= mag; } double pvx = pt.getKey() - lineStart.getKey(); double pvy = pt.getValue() - lineStart.getValue(); double pvdot = dx * pvx + dy * pvy; double ax = pvx - pvdot * dx; double ay = pvy - pvdot * dy; return Math.hypot(ax, ay); } private static void ramerDouglasPeucker(List<Point> pointList, double epsilon, List<Point> out) { if (pointList.size() < 2) throw new IllegalArgumentException("Not enough points to simplify"); double dmax = 0.0; int index = 0; int end = pointList.size() - 1; for (int i = 1; i < end; ++i) { double d = perpendicularDistance(pointList.get(i), pointList.get(0), pointList.get(end)); if (d > dmax) { index = i; dmax = d; } } if (dmax > epsilon) { List<Point> recResults1 = new ArrayList<>(); List<Point> recResults2 = new ArrayList<>(); List<Point> firstLine = pointList.subList(0, index + 1); List<Point> lastLine = pointList.subList(index, pointList.size()); ramerDouglasPeucker(firstLine, epsilon, recResults1); ramerDouglasPeucker(lastLine, epsilon, recResults2); out.addAll(recResults1.subList(0, recResults1.size() - 1)); out.addAll(recResults2); if (out.size() < 2) throw new RuntimeException("Problem assembling output"); } else { out.clear(); out.add(pointList.get(0)); out.add(pointList.get(pointList.size() - 1)); } } public static void main(String[] args) { List<Point> pointList = List.of( new Point(0.0, 0.0), new Point(1.0, 0.1), new Point(2.0, -0.1), new Point(3.0, 5.0), new Point(4.0, 6.0), new Point(5.0, 7.0), new Point(6.0, 8.1), new Point(7.0, 9.0), new Point(8.0, 9.0), new Point(9.0, 9.0) ); List<Point> pointListOut = new ArrayList<>(); ramerDouglasPeucker(pointList, 1.0, pointListOut); System.out.println("Points remaining after simplification:"); pointListOut.forEach(System.out::println); } }
func perpendicular_distance(Arr start, Arr end, Arr point) { ((point == start) || (point == end)) && return 0 var (Δx, Δy ) = ( end »-« start)... var (Δpx, Δpy) = (point »-« start)... var h = hypot(Δx, Δy) [\Δx, \Δy].map { *_ /= h } (([Δpx, Δpy] »-« ([Δx, Δy] »*» (Δx*Δpx + Δy*Δpy))) »**» 2).sum.sqrt } func Ramer_Douglas_Peucker(Arr points { .all { .len > 1 } }, ε = 1) { points.len == 2 && return points var d = (^points -> map { perpendicular_distance(points[0], points[-1], points[_]) }) if (d.max > ε) { var i = d.index(d.max) return [Ramer_Douglas_Peucker(points.ft(0, i), ε).ft(0, -2)..., Ramer_Douglas_Peucker(points.ft(i), ε)...] } return [points[0,-1]] } say Ramer_Douglas_Peucker( [[0,0],[1,0.1],[2,-0.1],[3,5],[4,6],[5,7],[6,8.1],[7,9],[8,9],[9,9]] )
Rewrite the snippet below in Ruby so it works the same as the original Java code.
import javax.imageio.ImageIO; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; public class BilinearInterpolation { private static int get(int self, int n) { return (self >> (n * 8)) & 0xFF; } private static float lerp(float s, float e, float t) { return s + (e - s) * t; } private static float blerp(final Float c00, float c10, float c01, float c11, float tx, float ty) { return lerp(lerp(c00, c10, tx), lerp(c01, c11, tx), ty); } private static BufferedImage scale(BufferedImage self, float scaleX, float scaleY) { int newWidth = (int) (self.getWidth() * scaleX); int newHeight = (int) (self.getHeight() * scaleY); BufferedImage newImage = new BufferedImage(newWidth, newHeight, self.getType()); for (int x = 0; x < newWidth; ++x) { for (int y = 0; y < newHeight; ++y) { float gx = ((float) x) / newWidth * (self.getWidth() - 1); float gy = ((float) y) / newHeight * (self.getHeight() - 1); int gxi = (int) gx; int gyi = (int) gy; int rgb = 0; int c00 = self.getRGB(gxi, gyi); int c10 = self.getRGB(gxi + 1, gyi); int c01 = self.getRGB(gxi, gyi + 1); int c11 = self.getRGB(gxi + 1, gyi + 1); for (int i = 0; i <= 2; ++i) { float b00 = get(c00, i); float b10 = get(c10, i); float b01 = get(c01, i); float b11 = get(c11, i); int ble = ((int) blerp(b00, b10, b01, b11, gx - gxi, gy - gyi)) << (8 * i); rgb = rgb | ble; } newImage.setRGB(x, y, rgb); } } return newImage; } public static void main(String[] args) throws IOException { File lenna = new File("Lenna100.jpg"); BufferedImage image = ImageIO.read(lenna); BufferedImage image2 = scale(image, 1.6f, 1.6f); File lenna2 = new File("Lenna100_larger.jpg"); ImageIO.write(image2, "jpg", lenna2); } }
require('Imager') func scale(img, scaleX, scaleY) { var (width, height) = (img.getwidth, img.getheight) var (newWidth, newHeight) = (int(width*scaleX), int(height*scaleY)) var out = %O<Imager>.new(xsize => newWidth, ysize => newHeight) var lerp = { |s, e, t| s + t*(e-s) } var blerp = { |c00, c10, c01, c11, tx, ty| lerp(lerp(c00, c10, tx), lerp(c01, c11, tx), ty) } for x,y in (^newWidth ~X ^newHeight) { var gxf = (x/newWidth * (width - 1)) var gyf = (y/newHeight * (height - 1)) var gx = gxf.int var gy = gyf.int var *c00 = img.getpixel(x => gx, y => gy ).rgba var *c10 = img.getpixel(x => gx+1, y => gy ).rgba var *c01 = img.getpixel(x => gx, y => gy+1).rgba var *c11 = img.getpixel(x => gx+1, y => gy+1).rgba var rgb = 3.of { |i| blerp(c00[i], c10[i], c01[i], c11[i], gxf - gx, gyf - gy).int } out.setpixel(x => x, y => y, color => rgb) } return out } var img = %O<Imager>.new(file => "input.png") var out = scale(img, 1.6, 1.6) out.write(file => "output.png")
Please provide an equivalent version of this Java code in Ruby.
import javax.imageio.ImageIO; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; public class BilinearInterpolation { private static int get(int self, int n) { return (self >> (n * 8)) & 0xFF; } private static float lerp(float s, float e, float t) { return s + (e - s) * t; } private static float blerp(final Float c00, float c10, float c01, float c11, float tx, float ty) { return lerp(lerp(c00, c10, tx), lerp(c01, c11, tx), ty); } private static BufferedImage scale(BufferedImage self, float scaleX, float scaleY) { int newWidth = (int) (self.getWidth() * scaleX); int newHeight = (int) (self.getHeight() * scaleY); BufferedImage newImage = new BufferedImage(newWidth, newHeight, self.getType()); for (int x = 0; x < newWidth; ++x) { for (int y = 0; y < newHeight; ++y) { float gx = ((float) x) / newWidth * (self.getWidth() - 1); float gy = ((float) y) / newHeight * (self.getHeight() - 1); int gxi = (int) gx; int gyi = (int) gy; int rgb = 0; int c00 = self.getRGB(gxi, gyi); int c10 = self.getRGB(gxi + 1, gyi); int c01 = self.getRGB(gxi, gyi + 1); int c11 = self.getRGB(gxi + 1, gyi + 1); for (int i = 0; i <= 2; ++i) { float b00 = get(c00, i); float b10 = get(c10, i); float b01 = get(c01, i); float b11 = get(c11, i); int ble = ((int) blerp(b00, b10, b01, b11, gx - gxi, gy - gyi)) << (8 * i); rgb = rgb | ble; } newImage.setRGB(x, y, rgb); } } return newImage; } public static void main(String[] args) throws IOException { File lenna = new File("Lenna100.jpg"); BufferedImage image = ImageIO.read(lenna); BufferedImage image2 = scale(image, 1.6f, 1.6f); File lenna2 = new File("Lenna100_larger.jpg"); ImageIO.write(image2, "jpg", lenna2); } }
require('Imager') func scale(img, scaleX, scaleY) { var (width, height) = (img.getwidth, img.getheight) var (newWidth, newHeight) = (int(width*scaleX), int(height*scaleY)) var out = %O<Imager>.new(xsize => newWidth, ysize => newHeight) var lerp = { |s, e, t| s + t*(e-s) } var blerp = { |c00, c10, c01, c11, tx, ty| lerp(lerp(c00, c10, tx), lerp(c01, c11, tx), ty) } for x,y in (^newWidth ~X ^newHeight) { var gxf = (x/newWidth * (width - 1)) var gyf = (y/newHeight * (height - 1)) var gx = gxf.int var gy = gyf.int var *c00 = img.getpixel(x => gx, y => gy ).rgba var *c10 = img.getpixel(x => gx+1, y => gy ).rgba var *c01 = img.getpixel(x => gx, y => gy+1).rgba var *c11 = img.getpixel(x => gx+1, y => gy+1).rgba var rgb = 3.of { |i| blerp(c00[i], c10[i], c01[i], c11[i], gxf - gx, gyf - gy).int } out.setpixel(x => x, y => y, color => rgb) } return out } var img = %O<Imager>.new(file => "input.png") var out = scale(img, 1.6, 1.6) out.write(file => "output.png")
Change the following Java code into Ruby without altering its purpose.
import java.util.Locale; public class Test { public static void main(String[] args) { System.out.println(new Vec2(5, 7).add(new Vec2(2, 3))); System.out.println(new Vec2(5, 7).sub(new Vec2(2, 3))); System.out.println(new Vec2(5, 7).mult(11)); System.out.println(new Vec2(5, 7).div(2)); } } class Vec2 { final double x, y; Vec2(double x, double y) { this.x = x; this.y = y; } Vec2 add(Vec2 v) { return new Vec2(x + v.x, y + v.y); } Vec2 sub(Vec2 v) { return new Vec2(x - v.x, y - v.y); } Vec2 div(double val) { return new Vec2(x / val, y / val); } Vec2 mult(double val) { return new Vec2(x * val, y * val); } @Override public String toString() { return String.format(Locale.US, "[%s, %s]", x, y); } }
class Vector def self.polar(r, angle=0) new(r*Math.cos(angle), r*Math.sin(angle)) end attr_reader :x, :y def initialize(x, y) raise TypeError unless x.is_a?(Numeric) and y.is_a?(Numeric) @x, @y = x, y end def +(other) raise TypeError if self.class != other.class self.class.new(@x + other.x, @y + other.y) end def -@; self.class.new(-@x, -@y) end def -(other) self + (-other) end def *(scalar) raise TypeError unless scalar.is_a?(Numeric) self.class.new(@x * scalar, @y * scalar) end def /(scalar) raise TypeError unless scalar.is_a?(Numeric) and scalar.nonzero? self.class.new(@x / scalar, @y / scalar) end def r; @r ||= Math.hypot(@x, @y) end def angle; @angle ||= Math.atan2(@y, @x) end def polar; [r, angle] end def rect; [@x, @y] end def to_s; " alias inspect to_s end p v = Vector.new(1,1) p w = Vector.new(3,4) p v + w p v - w p -v p w * 5 p w / 2.0 p w.x p w.y p v.polar p w.polar p z = Vector.polar(1, Math::PI/2) p z.rect p z.polar p z = Vector.polar(-2, Math::PI/4) p z.polar
Generate an equivalent Ruby version of this Java code.
import static java.lang.Math.*; import java.util.Locale; public class Test { public static void main(String[] args) { Pt a = Pt.fromY(1); Pt b = Pt.fromY(2); System.out.printf("a = %s%n", a); System.out.printf("b = %s%n", b); Pt c = a.plus(b); System.out.printf("c = a + b = %s%n", c); Pt d = c.neg(); System.out.printf("d = -c = %s%n", d); System.out.printf("c + d = %s%n", c.plus(d)); System.out.printf("a + b + d = %s%n", a.plus(b).plus(d)); System.out.printf("a * 12345 = %s%n", a.mult(12345)); } } class Pt { final static int bCoeff = 7; double x, y; Pt(double x, double y) { this.x = x; this.y = y; } static Pt zero() { return new Pt(Double.POSITIVE_INFINITY, Double.POSITIVE_INFINITY); } boolean isZero() { return this.x > 1e20 || this.x < -1e20; } static Pt fromY(double y) { return new Pt(cbrt(pow(y, 2) - bCoeff), y); } Pt dbl() { if (isZero()) return this; double L = (3 * this.x * this.x) / (2 * this.y); double x2 = pow(L, 2) - 2 * this.x; return new Pt(x2, L * (this.x - x2) - this.y); } Pt neg() { return new Pt(this.x, -this.y); } Pt plus(Pt q) { if (this.x == q.x && this.y == q.y) return dbl(); if (isZero()) return q; if (q.isZero()) return this; double L = (q.y - this.y) / (q.x - this.x); double xx = pow(L, 2) - this.x - q.x; return new Pt(xx, L * (this.x - xx) - this.y); } Pt mult(int n) { Pt r = Pt.zero(); Pt p = this; for (int i = 1; i <= n; i <<= 1) { if ((i & n) != 0) r = r.plus(p); p = p.dbl(); } return r; } @Override public String toString() { if (isZero()) return "Zero"; return String.format(Locale.US, "(%.3f,%.3f)", this.x, this.y); } }
module EC { var A = 0 var B = 7 class Horizon { method to_s { "EC Point at horizon" } method *(_) { self } method -(_) { self } } class Point(Number x, Number y) { method to_s { "EC Point at x= } method neg { Point(x, -y) } method -(Point p) { self + -p } method +(Point p) { if (x == p.x) { return (y == p.y ? self*2 : Horizon()) } else { var slope = (p.y - y)/(p.x - x) var x2 = (slope**2 - x - p.x) var y2 = (slope * (x - x2) - y) Point(x2, y2) } } method +(Horizon _) { self } method *((0)) { Horizon() } method *((1)) { self } method *((2)) { var l = (3 * x**2 + A)/(2 * y) var x2 = (l**2 - 2*x) var y2 = (l * (x - x2) - y) Point(x2, y2) } method *(Number n) { 2*(self * (n>>1)) + self*(n % 2) } } class Horizon { method +(Point p) { p } } class Number { method +(Point p) { p + self } method *(Point p) { p * self } method *(Horizon h) { h } method -(Point p) { -p + self } } } say var p = with(1) {|v| EC::Point(v, sqrt(abs(1 - v**3 - EC::A*v - EC::B))) } say var q = with(2) {|v| EC::Point(v, sqrt(abs(1 - v**3 - EC::A*v - EC::B))) } say var s = (p + q) say ("checking alignment: ", abs((p.x - q.x)*(-s.y - q.y) - (p.y - q.y)*(s.x - q.x)) < 1e-20)
Change the programming language of this snippet from Java to Ruby without modifying what it does.
import static java.lang.Math.*; import java.util.Locale; public class Test { public static void main(String[] args) { Pt a = Pt.fromY(1); Pt b = Pt.fromY(2); System.out.printf("a = %s%n", a); System.out.printf("b = %s%n", b); Pt c = a.plus(b); System.out.printf("c = a + b = %s%n", c); Pt d = c.neg(); System.out.printf("d = -c = %s%n", d); System.out.printf("c + d = %s%n", c.plus(d)); System.out.printf("a + b + d = %s%n", a.plus(b).plus(d)); System.out.printf("a * 12345 = %s%n", a.mult(12345)); } } class Pt { final static int bCoeff = 7; double x, y; Pt(double x, double y) { this.x = x; this.y = y; } static Pt zero() { return new Pt(Double.POSITIVE_INFINITY, Double.POSITIVE_INFINITY); } boolean isZero() { return this.x > 1e20 || this.x < -1e20; } static Pt fromY(double y) { return new Pt(cbrt(pow(y, 2) - bCoeff), y); } Pt dbl() { if (isZero()) return this; double L = (3 * this.x * this.x) / (2 * this.y); double x2 = pow(L, 2) - 2 * this.x; return new Pt(x2, L * (this.x - x2) - this.y); } Pt neg() { return new Pt(this.x, -this.y); } Pt plus(Pt q) { if (this.x == q.x && this.y == q.y) return dbl(); if (isZero()) return q; if (q.isZero()) return this; double L = (q.y - this.y) / (q.x - this.x); double xx = pow(L, 2) - this.x - q.x; return new Pt(xx, L * (this.x - xx) - this.y); } Pt mult(int n) { Pt r = Pt.zero(); Pt p = this; for (int i = 1; i <= n; i <<= 1) { if ((i & n) != 0) r = r.plus(p); p = p.dbl(); } return r; } @Override public String toString() { if (isZero()) return "Zero"; return String.format(Locale.US, "(%.3f,%.3f)", this.x, this.y); } }
module EC { var A = 0 var B = 7 class Horizon { method to_s { "EC Point at horizon" } method *(_) { self } method -(_) { self } } class Point(Number x, Number y) { method to_s { "EC Point at x= } method neg { Point(x, -y) } method -(Point p) { self + -p } method +(Point p) { if (x == p.x) { return (y == p.y ? self*2 : Horizon()) } else { var slope = (p.y - y)/(p.x - x) var x2 = (slope**2 - x - p.x) var y2 = (slope * (x - x2) - y) Point(x2, y2) } } method +(Horizon _) { self } method *((0)) { Horizon() } method *((1)) { self } method *((2)) { var l = (3 * x**2 + A)/(2 * y) var x2 = (l**2 - 2*x) var y2 = (l * (x - x2) - y) Point(x2, y2) } method *(Number n) { 2*(self * (n>>1)) + self*(n % 2) } } class Horizon { method +(Point p) { p } } class Number { method +(Point p) { p + self } method *(Point p) { p * self } method *(Horizon h) { h } method -(Point p) { -p + self } } } say var p = with(1) {|v| EC::Point(v, sqrt(abs(1 - v**3 - EC::A*v - EC::B))) } say var q = with(2) {|v| EC::Point(v, sqrt(abs(1 - v**3 - EC::A*v - EC::B))) } say var s = (p + q) say ("checking alignment: ", abs((p.x - q.x)*(-s.y - q.y) - (p.y - q.y)*(s.x - q.x)) < 1e-20)
Produce a functionally identical Ruby code for the snippet given in Java.
import static java.lang.Math.*; import java.util.function.Function; public class ChebyshevCoefficients { static double map(double x, double min_x, double max_x, double min_to, double max_to) { return (x - min_x) / (max_x - min_x) * (max_to - min_to) + min_to; } static void chebyshevCoef(Function<Double, Double> func, double min, double max, double[] coef) { int N = coef.length; for (int i = 0; i < N; i++) { double m = map(cos(PI * (i + 0.5f) / N), -1, 1, min, max); double f = func.apply(m) * 2 / N; for (int j = 0; j < N; j++) { coef[j] += f * cos(PI * j * (i + 0.5f) / N); } } } public static void main(String[] args) { final int N = 10; double[] c = new double[N]; double min = 0, max = 1; chebyshevCoef(x -> cos(x), min, max, c); System.out.println("Coefficients:"); for (double d : c) System.out.println(d); } }
def mapp(x, min_x, max_x, min_to, max_to) return (x - min_x) / (max_x - min_x) * (max_to - min_to) + min_to end def chebyshevCoef(func, min, max, coef) n = coef.length for i in 0 .. n-1 do m = mapp(Math.cos(Math::PI * (i + 0.5) / n), -1, 1, min, max) f = func.call(m) * 2 / n for j in 0 .. n-1 do coef[j] = coef[j] + f * Math.cos(Math::PI * j * (i + 0.5) / n) end end end N = 10 def main c = Array.new(N, 0) min = 0 max = 1 chebyshevCoef(lambda { |x| Math.cos(x) }, min, max, c) puts "Coefficients:" puts c end main()
Keep all operations the same but rewrite the snippet in Ruby.
import static java.lang.Math.*; import java.util.function.Function; public class ChebyshevCoefficients { static double map(double x, double min_x, double max_x, double min_to, double max_to) { return (x - min_x) / (max_x - min_x) * (max_to - min_to) + min_to; } static void chebyshevCoef(Function<Double, Double> func, double min, double max, double[] coef) { int N = coef.length; for (int i = 0; i < N; i++) { double m = map(cos(PI * (i + 0.5f) / N), -1, 1, min, max); double f = func.apply(m) * 2 / N; for (int j = 0; j < N; j++) { coef[j] += f * cos(PI * j * (i + 0.5f) / N); } } } public static void main(String[] args) { final int N = 10; double[] c = new double[N]; double min = 0, max = 1; chebyshevCoef(x -> cos(x), min, max, c); System.out.println("Coefficients:"); for (double d : c) System.out.println(d); } }
def mapp(x, min_x, max_x, min_to, max_to) return (x - min_x) / (max_x - min_x) * (max_to - min_to) + min_to end def chebyshevCoef(func, min, max, coef) n = coef.length for i in 0 .. n-1 do m = mapp(Math.cos(Math::PI * (i + 0.5) / n), -1, 1, min, max) f = func.call(m) * 2 / n for j in 0 .. n-1 do coef[j] = coef[j] + f * Math.cos(Math::PI * j * (i + 0.5) / n) end end end N = 10 def main c = Array.new(N, 0) min = 0 max = 1 chebyshevCoef(lambda { |x| Math.cos(x) }, min, max, c) puts "Coefficients:" puts c end main()
Can you help me rewrite this code in Ruby instead of Java, keeping it the same logically?
import java.util.ArrayList; import java.util.List; public class BWT { private static final String STX = "\u0002"; private static final String ETX = "\u0003"; private static String bwt(String s) { if (s.contains(STX) || s.contains(ETX)) { throw new IllegalArgumentException("String cannot contain STX or ETX"); } String ss = STX + s + ETX; List<String> table = new ArrayList<>(); for (int i = 0; i < ss.length(); i++) { String before = ss.substring(i); String after = ss.substring(0, i); table.add(before + after); } table.sort(String::compareTo); StringBuilder sb = new StringBuilder(); for (String str : table) { sb.append(str.charAt(str.length() - 1)); } return sb.toString(); } private static String ibwt(String r) { int len = r.length(); List<String> table = new ArrayList<>(); for (int i = 0; i < len; ++i) { table.add(""); } for (int j = 0; j < len; ++j) { for (int i = 0; i < len; ++i) { table.set(i, r.charAt(i) + table.get(i)); } table.sort(String::compareTo); } for (String row : table) { if (row.endsWith(ETX)) { return row.substring(1, len - 1); } } return ""; } private static String makePrintable(String s) { return s.replace(STX, "^").replace(ETX, "|"); } public static void main(String[] args) { List<String> tests = List.of( "banana", "appellee", "dogwood", "TO BE OR NOT TO BE OR WANT TO BE OR NOT?", "SIX.MIXED.PIXIES.SIFT.SIXTY.PIXIE.DUST.BOXES", "\u0002ABC\u0003" ); for (String test : tests) { System.out.println(makePrintable(test)); System.out.print(" --> "); String t = ""; try { t = bwt(test); System.out.println(makePrintable(t)); } catch (IllegalArgumentException e) { System.out.println("ERROR: " + e.getMessage()); } String r = ibwt(t); System.out.printf(" --> %s\n\n", r); } } }
STX = "\u0002" ETX = "\u0003" def bwt(s) for c in s.split('') if c == STX or c == ETX then raise ArgumentError.new("Input can't contain STX or ETX") end end ss = ("%s%s%s" % [STX, s, ETX]).split('') table = [] for i in 0 .. ss.length - 1 table.append(ss.join) ss = ss.rotate(-1) end table = table.sort return table.map{ |e| e[-1] }.join end def ibwt(r) len = r.length table = [""] * len for i in 0 .. len - 1 for j in 0 .. len - 1 table[j] = r[j] + table[j] end table = table.sort end for row in table if row[-1] == ETX then return row[1 .. -2] end end return "" end def makePrintable(s) s = s.gsub(STX, "^") return s.gsub(ETX, "|") end def main tests = [ "banana", "appellee", "dogwood", "TO BE OR NOT TO BE OR WANT TO BE OR NOT?", "SIX.MIXED.PIXIES.SIFT.SIXTY.PIXIE.DUST.BOXES", "\u0002ABC\u0003" ] for test in tests print makePrintable(test), "\n" print " --> " begin t = bwt(test) print makePrintable(t), "\n" r = ibwt(t) print " --> ", r, "\n\n" rescue ArgumentError => e print e.message, "\n" print " -->\n\n" end end end main()
Port the provided Java code into Ruby while preserving the original functionality.
import java.util.ArrayList; import java.util.List; public class BWT { private static final String STX = "\u0002"; private static final String ETX = "\u0003"; private static String bwt(String s) { if (s.contains(STX) || s.contains(ETX)) { throw new IllegalArgumentException("String cannot contain STX or ETX"); } String ss = STX + s + ETX; List<String> table = new ArrayList<>(); for (int i = 0; i < ss.length(); i++) { String before = ss.substring(i); String after = ss.substring(0, i); table.add(before + after); } table.sort(String::compareTo); StringBuilder sb = new StringBuilder(); for (String str : table) { sb.append(str.charAt(str.length() - 1)); } return sb.toString(); } private static String ibwt(String r) { int len = r.length(); List<String> table = new ArrayList<>(); for (int i = 0; i < len; ++i) { table.add(""); } for (int j = 0; j < len; ++j) { for (int i = 0; i < len; ++i) { table.set(i, r.charAt(i) + table.get(i)); } table.sort(String::compareTo); } for (String row : table) { if (row.endsWith(ETX)) { return row.substring(1, len - 1); } } return ""; } private static String makePrintable(String s) { return s.replace(STX, "^").replace(ETX, "|"); } public static void main(String[] args) { List<String> tests = List.of( "banana", "appellee", "dogwood", "TO BE OR NOT TO BE OR WANT TO BE OR NOT?", "SIX.MIXED.PIXIES.SIFT.SIXTY.PIXIE.DUST.BOXES", "\u0002ABC\u0003" ); for (String test : tests) { System.out.println(makePrintable(test)); System.out.print(" --> "); String t = ""; try { t = bwt(test); System.out.println(makePrintable(t)); } catch (IllegalArgumentException e) { System.out.println("ERROR: " + e.getMessage()); } String r = ibwt(t); System.out.printf(" --> %s\n\n", r); } } }
STX = "\u0002" ETX = "\u0003" def bwt(s) for c in s.split('') if c == STX or c == ETX then raise ArgumentError.new("Input can't contain STX or ETX") end end ss = ("%s%s%s" % [STX, s, ETX]).split('') table = [] for i in 0 .. ss.length - 1 table.append(ss.join) ss = ss.rotate(-1) end table = table.sort return table.map{ |e| e[-1] }.join end def ibwt(r) len = r.length table = [""] * len for i in 0 .. len - 1 for j in 0 .. len - 1 table[j] = r[j] + table[j] end table = table.sort end for row in table if row[-1] == ETX then return row[1 .. -2] end end return "" end def makePrintable(s) s = s.gsub(STX, "^") return s.gsub(ETX, "|") end def main tests = [ "banana", "appellee", "dogwood", "TO BE OR NOT TO BE OR WANT TO BE OR NOT?", "SIX.MIXED.PIXIES.SIFT.SIXTY.PIXIE.DUST.BOXES", "\u0002ABC\u0003" ] for test in tests print makePrintable(test), "\n" print " --> " begin t = bwt(test) print makePrintable(t), "\n" r = ibwt(t) print " --> ", r, "\n\n" rescue ArgumentError => e print e.message, "\n" print " -->\n\n" end end end main()
Write the same code in Ruby as shown below in Java.
import java.util.Arrays; import java.util.Collections; import java.util.LinkedList; import java.util.List; import java.util.Random; public class CardShuffles{ private static final Random rand = new Random(); public static <T> LinkedList<T> riffleShuffle(List<T> list, int flips){ LinkedList<T> newList = new LinkedList<T>(); newList.addAll(list); for(int n = 0; n < flips; n++){ int cutPoint = newList.size() / 2 + (rand.nextBoolean() ? -1 : 1 ) * rand.nextInt((int)(newList.size() * 0.1)); List<T> left = new LinkedList<T>(); left.addAll(newList.subList(0, cutPoint)); List<T> right = new LinkedList<T>(); right.addAll(newList.subList(cutPoint, newList.size())); newList.clear(); while(left.size() > 0 && right.size() > 0){ if(rand.nextDouble() >= ((double)left.size() / right.size()) / 2){ newList.add(right.remove(0)); }else{ newList.add(left.remove(0)); } } if(left.size() > 0) newList.addAll(left); if(right.size() > 0) newList.addAll(right); } return newList; } public static <T> LinkedList<T> overhandShuffle(List<T> list, int passes){ LinkedList<T> mainHand = new LinkedList<T>(); mainHand.addAll(list); for(int n = 0; n < passes; n++){ LinkedList<T> otherHand = new LinkedList<T>(); while(mainHand.size() > 0){ int cutSize = rand.nextInt((int)(list.size() * 0.2)) + 1; LinkedList<T> temp = new LinkedList<T>(); for(int i = 0; i < cutSize && mainHand.size() > 0; i++){ temp.add(mainHand.remove()); } if(rand.nextDouble() >= 0.1){ otherHand.addAll(0, temp); }else{ otherHand.addAll(temp); } } mainHand = otherHand; } return mainHand; } public static void main(String[] args){ List<Integer> list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); list = riffleShuffle(list, 10); System.out.println(list + "\n"); list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); list = riffleShuffle(list, 1); System.out.println(list + "\n"); list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); list = overhandShuffle(list, 10); System.out.println(list + "\n"); list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); list = overhandShuffle(list, 1); System.out.println(list + "\n"); list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); Collections.shuffle(list); System.out.println(list + "\n"); } }
def riffle deck left, right = deck.partition{rand(10).odd?} new_deck = [] until ((left_card=left.pop).to_i + (right_card=right.shift).to_i).zero? do new_deck << left_card if left_card new_deck << right_card if right_card end new_deck end def overhand deck deck, new_deck = deck.dup, [] s = deck.size new_deck += deck.pop(rand(s * 0.2)) until deck.empty? new_deck end def bonus deck deck.sort { |a, b| Time.now.to_i % a <=> Time.now.to_i % b } end deck = [*1..20] p riffle(deck) p overhand(deck) p bonus(deck)
Translate the given Java code snippet into Ruby without altering its behavior.
import java.util.Arrays; import java.util.Collections; import java.util.LinkedList; import java.util.List; import java.util.Random; public class CardShuffles{ private static final Random rand = new Random(); public static <T> LinkedList<T> riffleShuffle(List<T> list, int flips){ LinkedList<T> newList = new LinkedList<T>(); newList.addAll(list); for(int n = 0; n < flips; n++){ int cutPoint = newList.size() / 2 + (rand.nextBoolean() ? -1 : 1 ) * rand.nextInt((int)(newList.size() * 0.1)); List<T> left = new LinkedList<T>(); left.addAll(newList.subList(0, cutPoint)); List<T> right = new LinkedList<T>(); right.addAll(newList.subList(cutPoint, newList.size())); newList.clear(); while(left.size() > 0 && right.size() > 0){ if(rand.nextDouble() >= ((double)left.size() / right.size()) / 2){ newList.add(right.remove(0)); }else{ newList.add(left.remove(0)); } } if(left.size() > 0) newList.addAll(left); if(right.size() > 0) newList.addAll(right); } return newList; } public static <T> LinkedList<T> overhandShuffle(List<T> list, int passes){ LinkedList<T> mainHand = new LinkedList<T>(); mainHand.addAll(list); for(int n = 0; n < passes; n++){ LinkedList<T> otherHand = new LinkedList<T>(); while(mainHand.size() > 0){ int cutSize = rand.nextInt((int)(list.size() * 0.2)) + 1; LinkedList<T> temp = new LinkedList<T>(); for(int i = 0; i < cutSize && mainHand.size() > 0; i++){ temp.add(mainHand.remove()); } if(rand.nextDouble() >= 0.1){ otherHand.addAll(0, temp); }else{ otherHand.addAll(temp); } } mainHand = otherHand; } return mainHand; } public static void main(String[] args){ List<Integer> list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); list = riffleShuffle(list, 10); System.out.println(list + "\n"); list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); list = riffleShuffle(list, 1); System.out.println(list + "\n"); list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); list = overhandShuffle(list, 10); System.out.println(list + "\n"); list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); list = overhandShuffle(list, 1); System.out.println(list + "\n"); list = Arrays.asList(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20); System.out.println(list); Collections.shuffle(list); System.out.println(list + "\n"); } }
def riffle deck left, right = deck.partition{rand(10).odd?} new_deck = [] until ((left_card=left.pop).to_i + (right_card=right.shift).to_i).zero? do new_deck << left_card if left_card new_deck << right_card if right_card end new_deck end def overhand deck deck, new_deck = deck.dup, [] s = deck.size new_deck += deck.pop(rand(s * 0.2)) until deck.empty? new_deck end def bonus deck deck.sort { |a, b| Time.now.to_i % a <=> Time.now.to_i % b } end deck = [*1..20] p riffle(deck) p overhand(deck) p bonus(deck)
Can you help me rewrite this code in Ruby instead of Java, keeping it the same logically?
import java.math.BigDecimal; import java.math.MathContext; import java.util.Arrays; import java.util.stream.LongStream; public class FaulhabersTriangle { private static final MathContext MC = new MathContext(256); private static long gcd(long a, long b) { if (b == 0) { return a; } return gcd(b, a % b); } private static class Frac implements Comparable<Frac> { private long num; private long denom; public static final Frac ZERO = new Frac(0, 1); public Frac(long n, long d) { if (d == 0) throw new IllegalArgumentException("d must not be zero"); long nn = n; long dd = d; if (nn == 0) { dd = 1; } else if (dd < 0) { nn = -nn; dd = -dd; } long g = Math.abs(gcd(nn, dd)); if (g > 1) { nn /= g; dd /= g; } num = nn; denom = dd; } public Frac plus(Frac rhs) { return new Frac(num * rhs.denom + denom * rhs.num, rhs.denom * denom); } public Frac unaryMinus() { return new Frac(-num, denom); } public Frac minus(Frac rhs) { return this.plus(rhs.unaryMinus()); } public Frac times(Frac rhs) { return new Frac(this.num * rhs.num, this.denom * rhs.denom); } @Override public int compareTo(Frac o) { double diff = toDouble() - o.toDouble(); return Double.compare(diff, 0.0); } @Override public boolean equals(Object obj) { return null != obj && obj instanceof Frac && this.compareTo((Frac) obj) == 0; } @Override public String toString() { if (denom == 1) { return Long.toString(num); } return String.format("%d/%d", num, denom); } public double toDouble() { return (double) num / denom; } public BigDecimal toBigDecimal() { return BigDecimal.valueOf(num).divide(BigDecimal.valueOf(denom), MC); } } private static Frac bernoulli(int n) { if (n < 0) throw new IllegalArgumentException("n may not be negative or zero"); Frac[] a = new Frac[n + 1]; Arrays.fill(a, Frac.ZERO); for (int m = 0; m <= n; ++m) { a[m] = new Frac(1, m + 1); for (int j = m; j >= 1; --j) { a[j - 1] = a[j - 1].minus(a[j]).times(new Frac(j, 1)); } } if (n != 1) return a[0]; return a[0].unaryMinus(); } private static long binomial(int n, int k) { if (n < 0 || k < 0 || n < k) throw new IllegalArgumentException(); if (n == 0 || k == 0) return 1; long num = LongStream.rangeClosed(k + 1, n).reduce(1, (a, b) -> a * b); long den = LongStream.rangeClosed(2, n - k).reduce(1, (acc, i) -> acc * i); return num / den; } private static Frac[] faulhaberTriangle(int p) { Frac[] coeffs = new Frac[p + 1]; Arrays.fill(coeffs, Frac.ZERO); Frac q = new Frac(1, p + 1); int sign = -1; for (int j = 0; j <= p; ++j) { sign *= -1; coeffs[p - j] = q.times(new Frac(sign, 1)).times(new Frac(binomial(p + 1, j), 1)).times(bernoulli(j)); } return coeffs; } public static void main(String[] args) { for (int i = 0; i <= 9; ++i) { Frac[] coeffs = faulhaberTriangle(i); for (Frac coeff : coeffs) { System.out.printf("%5s ", coeff); } System.out.println(); } System.out.println(); int k = 17; Frac[] cc = faulhaberTriangle(k); int n = 1000; BigDecimal nn = BigDecimal.valueOf(n); BigDecimal np = BigDecimal.ONE; BigDecimal sum = BigDecimal.ZERO; for (Frac c : cc) { np = np.multiply(nn); sum = sum.add(np.multiply(c.toBigDecimal())); } System.out.println(sum.toBigInteger()); } }
class Frac attr_accessor:num attr_accessor:denom def initialize(n,d) if d == 0 then raise ArgumentError.new('d cannot be zero') end nn = n dd = d if nn == 0 then dd = 1 elsif dd < 0 then nn = -nn dd = -dd end g = nn.abs.gcd(dd.abs) if g > 1 then nn = nn / g dd = dd / g end @num = nn @denom = dd end def to_s if self.denom == 1 then return self.num.to_s else return "%d/%d" % [self.num, self.denom] end end def -@ return Frac.new(-self.num, self.denom) end def +(rhs) return Frac.new(self.num * rhs.denom + self.denom * rhs.num, rhs.denom * self.denom) end def -(rhs) return Frac.new(self.num * rhs.denom - self.denom * rhs.num, rhs.denom * self.denom) end def *(rhs) return Frac.new(self.num * rhs.num, rhs.denom * self.denom) end end FRAC_ZERO = Frac.new(0, 1) FRAC_ONE = Frac.new(1, 1) def bernoulli(n) if n < 0 then raise ArgumentError.new('n cannot be negative') end a = Array.new(n + 1) a[0] = FRAC_ZERO for m in 0 .. n do a[m] = Frac.new(1, m + 1) m.downto(1) do |j| a[j - 1] = (a[j - 1] - a[j]) * Frac.new(j, 1) end end if n != 1 then return a[0] end return -a[0] end def binomial(n, k) if n < 0 then raise ArgumentError.new('n cannot be negative') end if k < 0 then raise ArgumentError.new('k cannot be negative') end if n < k then raise ArgumentError.new('n cannot be less than k') end if n == 0 or k == 0 then return 1 end num = 1 for i in k + 1 .. n do num = num * i end den = 1 for i in 2 .. n - k do den = den * i end return num / den end def faulhaberTriangle(p) coeffs = Array.new(p + 1) coeffs[0] = FRAC_ZERO q = Frac.new(1, p + 1) sign = -1 for j in 0 .. p do sign = -sign coeffs[p - j] = q * Frac.new(sign, 1) * Frac.new(binomial(p + 1, j), 1) * bernoulli(j) end return coeffs end def main for i in 0 .. 9 do coeffs = faulhaberTriangle(i) coeffs.each do |coeff| print "%5s " % [coeff] end puts end end main()
Transform the following Java implementation into Ruby, maintaining the same output and logic.
import java.math.BigInteger; import java.util.Arrays; class Test { final static int nMax = 250; final static int nBranches = 4; static BigInteger[] rooted = new BigInteger[nMax + 1]; static BigInteger[] unrooted = new BigInteger[nMax + 1]; static BigInteger[] c = new BigInteger[nBranches]; static void tree(int br, int n, int l, int inSum, BigInteger cnt) { int sum = inSum; for (int b = br + 1; b <= nBranches; b++) { sum += n; if (sum > nMax || (l * 2 >= sum && b >= nBranches)) return; BigInteger tmp = rooted[n]; if (b == br + 1) { c[br] = tmp.multiply(cnt); } else { c[br] = c[br].multiply(tmp.add(BigInteger.valueOf(b - br - 1))); c[br] = c[br].divide(BigInteger.valueOf(b - br)); } if (l * 2 < sum) unrooted[sum] = unrooted[sum].add(c[br]); if (b < nBranches) rooted[sum] = rooted[sum].add(c[br]); for (int m = n - 1; m > 0; m--) tree(b, m, l, sum, c[br]); } } static void bicenter(int s) { if ((s & 1) == 0) { BigInteger tmp = rooted[s / 2]; tmp = tmp.add(BigInteger.ONE).multiply(rooted[s / 2]); unrooted[s] = unrooted[s].add(tmp.shiftRight(1)); } } public static void main(String[] args) { Arrays.fill(rooted, BigInteger.ZERO); Arrays.fill(unrooted, BigInteger.ZERO); rooted[0] = rooted[1] = BigInteger.ONE; unrooted[0] = unrooted[1] = BigInteger.ONE; for (int n = 1; n <= nMax; n++) { tree(0, n, n, 1, BigInteger.ONE); bicenter(n); System.out.printf("%d: %s%n", n, unrooted[n]); } } }
MAX_N = 500 BRANCH = 4 def tree(br, n, l=n, sum=1, cnt=1) for b in br+1 .. BRANCH sum += n return if sum >= MAX_N return if l * 2 >= sum and b >= BRANCH if b == br + 1 c = $ra[n] * cnt else c = c * ($ra[n] + (b - br - 1)) / (b - br) end $unrooted[sum] += c if l * 2 < sum next if b >= BRANCH $ra[sum] += c (1...n).each {|m| tree(b, m, l, sum, c)} end end def bicenter(s) return if s.odd? aux = $ra[s / 2] $unrooted[s] += aux * (aux + 1) / 2 end $ra = [0] * MAX_N $unrooted = [0] * MAX_N $ra[0] = $ra[1] = $unrooted[0] = $unrooted[1] = 1 for n in 1...MAX_N tree(0, n) bicenter(n) puts "%d: %d" % [n, $unrooted[n]] end
Preserve the algorithm and functionality while converting the code from Java to Ruby.
import java.math.BigInteger; import java.util.Arrays; class Test { final static int nMax = 250; final static int nBranches = 4; static BigInteger[] rooted = new BigInteger[nMax + 1]; static BigInteger[] unrooted = new BigInteger[nMax + 1]; static BigInteger[] c = new BigInteger[nBranches]; static void tree(int br, int n, int l, int inSum, BigInteger cnt) { int sum = inSum; for (int b = br + 1; b <= nBranches; b++) { sum += n; if (sum > nMax || (l * 2 >= sum && b >= nBranches)) return; BigInteger tmp = rooted[n]; if (b == br + 1) { c[br] = tmp.multiply(cnt); } else { c[br] = c[br].multiply(tmp.add(BigInteger.valueOf(b - br - 1))); c[br] = c[br].divide(BigInteger.valueOf(b - br)); } if (l * 2 < sum) unrooted[sum] = unrooted[sum].add(c[br]); if (b < nBranches) rooted[sum] = rooted[sum].add(c[br]); for (int m = n - 1; m > 0; m--) tree(b, m, l, sum, c[br]); } } static void bicenter(int s) { if ((s & 1) == 0) { BigInteger tmp = rooted[s / 2]; tmp = tmp.add(BigInteger.ONE).multiply(rooted[s / 2]); unrooted[s] = unrooted[s].add(tmp.shiftRight(1)); } } public static void main(String[] args) { Arrays.fill(rooted, BigInteger.ZERO); Arrays.fill(unrooted, BigInteger.ZERO); rooted[0] = rooted[1] = BigInteger.ONE; unrooted[0] = unrooted[1] = BigInteger.ONE; for (int n = 1; n <= nMax; n++) { tree(0, n, n, 1, BigInteger.ONE); bicenter(n); System.out.printf("%d: %s%n", n, unrooted[n]); } } }
MAX_N = 500 BRANCH = 4 def tree(br, n, l=n, sum=1, cnt=1) for b in br+1 .. BRANCH sum += n return if sum >= MAX_N return if l * 2 >= sum and b >= BRANCH if b == br + 1 c = $ra[n] * cnt else c = c * ($ra[n] + (b - br - 1)) / (b - br) end $unrooted[sum] += c if l * 2 < sum next if b >= BRANCH $ra[sum] += c (1...n).each {|m| tree(b, m, l, sum, c)} end end def bicenter(s) return if s.odd? aux = $ra[s / 2] $unrooted[s] += aux * (aux + 1) / 2 end $ra = [0] * MAX_N $unrooted = [0] * MAX_N $ra[0] = $ra[1] = $unrooted[0] = $unrooted[1] = 1 for n in 1...MAX_N tree(0, n) bicenter(n) puts "%d: %d" % [n, $unrooted[n]] end
Rewrite the snippet below in Ruby so it works the same as the original Java code.
import java.util.Arrays; import java.util.stream.IntStream; public class FaulhabersFormula { private static long gcd(long a, long b) { if (b == 0) { return a; } return gcd(b, a % b); } private static class Frac implements Comparable<Frac> { private long num; private long denom; public static final Frac ZERO = new Frac(0, 1); public static final Frac ONE = new Frac(1, 1); public Frac(long n, long d) { if (d == 0) throw new IllegalArgumentException("d must not be zero"); long nn = n; long dd = d; if (nn == 0) { dd = 1; } else if (dd < 0) { nn = -nn; dd = -dd; } long g = Math.abs(gcd(nn, dd)); if (g > 1) { nn /= g; dd /= g; } num = nn; denom = dd; } public Frac plus(Frac rhs) { return new Frac(num * rhs.denom + denom * rhs.num, rhs.denom * denom); } public Frac unaryMinus() { return new Frac(-num, denom); } public Frac minus(Frac rhs) { return this.plus(rhs.unaryMinus()); } public Frac times(Frac rhs) { return new Frac(this.num * rhs.num, this.denom * rhs.denom); } @Override public int compareTo(Frac o) { double diff = toDouble() - o.toDouble(); return Double.compare(diff, 0.0); } @Override public boolean equals(Object obj) { return null != obj && obj instanceof Frac && this.compareTo((Frac) obj) == 0; } @Override public String toString() { if (denom == 1) { return Long.toString(num); } return String.format("%d/%d", num, denom); } private double toDouble() { return (double) num / denom; } } private static Frac bernoulli(int n) { if (n < 0) throw new IllegalArgumentException("n may not be negative or zero"); Frac[] a = new Frac[n + 1]; Arrays.fill(a, Frac.ZERO); for (int m = 0; m <= n; ++m) { a[m] = new Frac(1, m + 1); for (int j = m; j >= 1; --j) { a[j - 1] = a[j - 1].minus(a[j]).times(new Frac(j, 1)); } } if (n != 1) return a[0]; return a[0].unaryMinus(); } private static int binomial(int n, int k) { if (n < 0 || k < 0 || n < k) throw new IllegalArgumentException(); if (n == 0 || k == 0) return 1; int num = IntStream.rangeClosed(k + 1, n).reduce(1, (a, b) -> a * b); int den = IntStream.rangeClosed(2, n - k).reduce(1, (acc, i) -> acc * i); return num / den; } private static void faulhaber(int p) { System.out.printf("%d : ", p); Frac q = new Frac(1, p + 1); int sign = -1; for (int j = 0; j <= p; ++j) { sign *= -1; Frac coeff = q.times(new Frac(sign, 1)).times(new Frac(binomial(p + 1, j), 1)).times(bernoulli(j)); if (Frac.ZERO.equals(coeff)) continue; if (j == 0) { if (!Frac.ONE.equals(coeff)) { if (Frac.ONE.unaryMinus().equals(coeff)) { System.out.print("-"); } else { System.out.print(coeff); } } } else { if (Frac.ONE.equals(coeff)) { System.out.print(" + "); } else if (Frac.ONE.unaryMinus().equals(coeff)) { System.out.print(" - "); } else if (coeff.compareTo(Frac.ZERO) > 0) { System.out.printf(" + %s", coeff); } else { System.out.printf(" - %s", coeff.unaryMinus()); } } int pwr = p + 1 - j; if (pwr > 1) System.out.printf("n^%d", pwr); else System.out.print("n"); } System.out.println(); } public static void main(String[] args) { for (int i = 0; i <= 9; ++i) { faulhaber(i); } } }
def binomial(n,k) if n < 0 or k < 0 or n < k then return -1 end if n == 0 or k == 0 then return 1 end num = 1 for i in k+1 .. n do num = num * i end denom = 1 for i in 2 .. n-k do denom = denom * i end return num / denom end def bernoulli(n) if n < 0 then raise "n cannot be less than zero" end a = Array.new(16) for m in 0 .. n do a[m] = Rational(1, m + 1) for j in m.downto(1) do a[j-1] = (a[j-1] - a[j]) * Rational(j) end end if n != 1 then return a[0] end return -a[0] end def faulhaber(p) print("%d : " % [p]) q = Rational(1, p + 1) sign = -1 for j in 0 .. p do sign = -1 * sign coeff = q * Rational(sign) * Rational(binomial(p+1, j)) * bernoulli(j) if coeff == 0 then next end if j == 0 then if coeff != 1 then if coeff == -1 then print "-" else print coeff end end else if coeff == 1 then print " + " elsif coeff == -1 then print " - " elsif 0 < coeff then print " + " print coeff else print " - " print -coeff end end pwr = p + 1 - j if pwr > 1 then print "n^%d" % [pwr] else print "n" end end print "\n" end def main for i in 0 .. 9 do faulhaber(i) end end main()
Write the same algorithm in Ruby as shown in this Java implementation.
import java.io.IOException; import org.apache.directory.api.ldap.model.cursor.CursorException; import org.apache.directory.api.ldap.model.cursor.EntryCursor; import org.apache.directory.api.ldap.model.entry.Entry; import org.apache.directory.api.ldap.model.exception.LdapException; import org.apache.directory.api.ldap.model.message.SearchScope; import org.apache.directory.ldap.client.api.LdapConnection; import org.apache.directory.ldap.client.api.LdapNetworkConnection; public class LdapSearchDemo { public static void main(String[] args) throws IOException, LdapException, CursorException { new LdapSearchDemo().demonstrateSearch(); } private void demonstrateSearch() throws IOException, LdapException, CursorException { try (LdapConnection conn = new LdapNetworkConnection("localhost", 11389)) { conn.bind("uid=admin,ou=system", "********"); search(conn, "*mil*"); conn.unBind(); } } private void search(LdapConnection connection, String uid) throws LdapException, CursorException { String baseDn = "ou=users,o=mojo"; String filter = "(&(objectClass=person)(&(uid=" + uid + ")))"; SearchScope scope = SearchScope.SUBTREE; String[] attributes = {"dn", "cn", "sn", "uid"}; int ksearch = 0; EntryCursor cursor = connection.search(baseDn, filter, scope, attributes); while (cursor.next()) { ksearch++; Entry entry = cursor.get(); System.out.printf("Search entry %d = %s%n", ksearch, entry); } } }
require 'rubygems' require 'net/ldap' ldap = Net::LDAP.new(:host => 'hostname', :base => 'base') ldap.authenticate('bind_dn', 'bind_pass') filter = Net::LDAP::Filter.pres('objectclass') filter &= Net::LDAP::Filter.eq('sn','Jackman') filter = Net::LDAP::Filter.construct('(&(objectclass=*)(sn=Jackman))') results = ldap.search(:filter => filter) puts results[0][:sn]
Convert this Java block to Ruby, preserving its control flow and logic.
public class PrimeConspiracy { public static void main(String[] args) { final int limit = 1000_000; final int sieveLimit = 15_500_000; int[][] buckets = new int[10][10]; int prevDigit = 2; boolean[] notPrime = sieve(sieveLimit); for (int n = 3, primeCount = 1; primeCount < limit; n++) { if (notPrime[n]) continue; int digit = n % 10; buckets[prevDigit][digit]++; prevDigit = digit; primeCount++; } for (int i = 0; i < 10; i++) { for (int j = 0; j < 10; j++) { if (buckets[i][j] != 0) { System.out.printf("%d -> %d : %2f%n", i, j, buckets[i][j] / (limit / 100.0)); } } } } public static boolean[] sieve(int limit) { boolean[] composite = new boolean[limit]; composite[0] = composite[1] = true; int max = (int) Math.sqrt(limit); for (int n = 2; n <= max; n++) { if (!composite[n]) { for (int k = n * n; k < limit; k += n) { composite[k] = true; } } } return composite; } }
require "prime" def prime_conspiracy(m) conspiracy = Hash.new(0) Prime.take(m).map{|n| n%10}.each_cons(2){|a,b| conspiracy[[a,b]] += 1} puts " conspiracy.sort.each do |(a,b),v| puts "%d → %d count:%10d frequency:%7.4f %" % [a, b, v, 100.0*v/m] end end prime_conspiracy(1_000_000)
Convert this Java block to Ruby, preserving its control flow and logic.
import java.util.ArrayList; import java.util.List; public class ListRootedTrees { private static final List<Long> TREE_LIST = new ArrayList<>(); private static final List<Integer> OFFSET = new ArrayList<>(); static { for (int i = 0; i < 32; i++) { if (i == 1) { OFFSET.add(1); } else { OFFSET.add(0); } } } private static void append(long t) { TREE_LIST.add(1 | (t << 1)); } private static void show(long t, int l) { while (l-- > 0) { if (t % 2 == 1) { System.out.print('('); } else { System.out.print(')'); } t = t >> 1; } } private static void listTrees(int n) { for (int i = OFFSET.get(n); i < OFFSET.get(n + 1); i++) { show(TREE_LIST.get(i), n * 2); System.out.println(); } } private static void assemble(int n, long t, int sl, int pos, int rem) { if (rem == 0) { append(t); return; } var pp = pos; var ss = sl; if (sl > rem) { ss = rem; pp = OFFSET.get(ss); } else if (pp >= OFFSET.get(ss + 1)) { ss--; if (ss == 0) { return; } pp = OFFSET.get(ss); } assemble(n, t << (2 * ss) | TREE_LIST.get(pp), ss, pp, rem - ss); assemble(n, t, ss, pp + 1, rem); } private static void makeTrees(int n) { if (OFFSET.get(n + 1) != 0) { return; } if (n > 0) { makeTrees(n - 1); } assemble(n, 0, n - 1, OFFSET.get(n - 1), n - 1); OFFSET.set(n + 1, TREE_LIST.size()); } private static void test(int n) { if (n < 1 || n > 12) { throw new IllegalArgumentException("Argument must be between 1 and 12"); } append(0); makeTrees(n); System.out.printf("Number of %d-trees: %d\n", n, OFFSET.get(n + 1) - OFFSET.get(n)); listTrees(n); } public static void main(String[] args) { test(5); } }
TREE_LIST = [] OFFSET = [] for i in 0..31 if i == 1 then OFFSET << 1 else OFFSET << 0 end end def append(t) TREE_LIST << (1 | (t << 1)) end def show(t, l) while l > 0 l = l - 1 if t % 2 == 1 then print '(' else print ')' end t = t >> 1 end end def listTrees(n) for i in OFFSET[n] .. OFFSET[n + 1] - 1 show(TREE_LIST[i], n * 2) print "\n" end end def assemble(n, t, sl, pos, rem) if rem == 0 then append(t) return end if sl > rem then sl = rem pos = OFFSET[sl] elsif pos >= OFFSET[sl + 1] then sl = sl - 1 if sl == 0 then return end pos = OFFSET[sl] end assemble(n, t << (2 * sl) | TREE_LIST[pos], sl, pos, rem - sl) assemble(n, t, sl, pos + 1, rem) end def makeTrees(n) if OFFSET[n + 1] != 0 then return end if n > 0 then makeTrees(n - 1) end assemble(n, 0, n - 1, OFFSET[n - 1], n - 1) OFFSET[n + 1] = TREE_LIST.length() end def test(n) if n < 1 || n > 12 then raise ArgumentError.new("Argument must be between 1 and 12") end append(0) makeTrees(n) print "Number of %d-trees: %d\n" % [n, OFFSET[n + 1] - OFFSET[n]] listTrees(n) end test(5)
Translate this program into Ruby but keep the logic exactly as in Java.
import java.util.ArrayList; import java.util.Collections; import java.util.List; public class LuckyNumbers { private static int MAX = 200000; private static List<Integer> luckyEven = luckyNumbers(MAX, true); private static List<Integer> luckyOdd = luckyNumbers(MAX, false); public static void main(String[] args) { if ( args.length == 1 || ( args.length == 2 && args[1].compareTo("lucky") == 0 ) ) { int n = Integer.parseInt(args[0]); System.out.printf("LuckyNumber(%d) = %d%n", n, luckyOdd.get(n-1)); } else if ( args.length == 2 && args[1].compareTo("evenLucky") == 0 ) { int n = Integer.parseInt(args[0]); System.out.printf("EvenLuckyNumber(%d) = %d%n", n, luckyEven.get(n-1)); } else if ( args.length == 2 || args.length == 3 ) { int j = Integer.parseInt(args[0]); int k = Integer.parseInt(args[1]); if ( ( args.length == 2 && k > 0 ) || (args.length == 3 && k > 0 && args[2].compareTo("lucky") == 0 ) ) { System.out.printf("LuckyNumber(%d) through LuckyNumber(%d) = %s%n", j, k, luckyOdd.subList(j-1, k)); } else if ( args.length == 3 && k > 0 && args[2].compareTo("evenLucky") == 0 ) { System.out.printf("EvenLuckyNumber(%d) through EvenLuckyNumber(%d) = %s%n", j, k, luckyEven.subList(j-1, k)); } else if ( ( args.length == 2 && k < 0 ) || (args.length == 3 && k < 0 && args[2].compareTo("lucky") == 0 ) ) { int n = Collections.binarySearch(luckyOdd, j); int m = Collections.binarySearch(luckyOdd, -k); System.out.printf("Lucky Numbers in the range %d to %d inclusive = %s%n", j, -k, luckyOdd.subList(n < 0 ? -n-1 : n, m < 0 ? -m-1 : m+1)); } else if ( args.length == 3 && k < 0 && args[2].compareTo("evenLucky") == 0 ) { int n = Collections.binarySearch(luckyEven, j); int m = Collections.binarySearch(luckyEven, -k); System.out.printf("Even Lucky Numbers in the range %d to %d inclusive = %s%n", j, -k, luckyEven.subList(n < 0 ? -n-1 : n, m < 0 ? -m-1 : m+1)); } } } private static List<Integer> luckyNumbers(int max, boolean even) { List<Integer> luckyList = new ArrayList<>(); for ( int i = even ? 2 : 1 ; i <= max ; i += 2 ) { luckyList.add(i); } int start = 1; boolean removed = true; while ( removed ) { removed = false; int increment = luckyList.get(start); List<Integer> remove = new ArrayList<>(); for ( int i = increment-1 ; i < luckyList.size() ; i += increment ) { remove.add(0, i); removed = true; } for ( int i : remove ) { luckyList.remove(i); } start++; } return luckyList; } }
def generator(even=false, nmax=1000000) start = even ? 2 : 1 Enumerator.new do |y| n = 1 ary = [0] + (start..nmax).step(2).to_a y << ary[n] while (m = ary[n+=1]) < ary.size y << m (m...ary.size).step(m){|i| ary[i]=nil} ary.compact! end ary[n..-1].each{|i| y << i} raise StopIteration end end def lucky(argv) j, k = argv[0].to_i, argv[1].to_i mode = /even/i=~argv[2] ? :'even lucky' : :lucky seq = generator(mode == :'even lucky') ord = ->(n){" if k.zero? puts " elsif 0 < k puts " " else k = -k ary = [] loop do case num=seq.next when 1...j when j..k then ary << num else break end end puts "all " end end if __FILE__ == $0 lucky(ARGV) end
Rewrite the snippet below in Ruby so it works the same as the original Java code.
public class ImaginaryBaseNumber { private static class Complex { private Double real, imag; public Complex(double r, double i) { this.real = r; this.imag = i; } public Complex(int r, int i) { this.real = (double) r; this.imag = (double) i; } public Complex add(Complex rhs) { return new Complex( real + rhs.real, imag + rhs.imag ); } public Complex times(Complex rhs) { return new Complex( real * rhs.real - imag * rhs.imag, real * rhs.imag + imag * rhs.real ); } public Complex times(double rhs) { return new Complex( real * rhs, imag * rhs ); } public Complex inv() { double denom = real * real + imag * imag; return new Complex( real / denom, -imag / denom ); } public Complex unaryMinus() { return new Complex(-real, -imag); } public Complex divide(Complex rhs) { return this.times(rhs.inv()); } public QuaterImaginary toQuaterImaginary() { if (real == 0.0 && imag == 0.0) return new QuaterImaginary("0"); int re = real.intValue(); int im = imag.intValue(); int fi = -1; StringBuilder sb = new StringBuilder(); while (re != 0) { int rem = re % -4; re /= -4; if (rem < 0) { rem += 4; re++; } sb.append(rem); sb.append(0); } if (im != 0) { Double f = new Complex(0.0, imag).divide(new Complex(0.0, 2.0)).real; im = ((Double) Math.ceil(f)).intValue(); f = -4.0 * (f - im); int index = 1; while (im != 0) { int rem = im % -4; im /= -4; if (rem < 0) { rem += 4; im++; } if (index < sb.length()) { sb.setCharAt(index, (char) (rem + 48)); } else { sb.append(0); sb.append(rem); } index += 2; } fi = f.intValue(); } sb.reverse(); if (fi != -1) sb.append(".").append(fi); while (sb.charAt(0) == '0') sb.deleteCharAt(0); if (sb.charAt(0) == '.') sb.insert(0, '0'); return new QuaterImaginary(sb.toString()); } @Override public String toString() { double real2 = real == -0.0 ? 0.0 : real; double imag2 = imag == -0.0 ? 0.0 : imag; String result = imag2 >= 0.0 ? String.format("%.0f + %.0fi", real2, imag2) : String.format("%.0f - %.0fi", real2, -imag2); result = result.replace(".0 ", " ").replace(".0i", "i").replace(" + 0i", ""); if (result.startsWith("0 + ")) result = result.substring(4); if (result.startsWith("0 - ")) result = result.substring(4); return result; } } private static class QuaterImaginary { private static final Complex TWOI = new Complex(0.0, 2.0); private static final Complex INVTWOI = TWOI.inv(); private String b2i; public QuaterImaginary(String b2i) { if (b2i.equals("") || !b2i.chars().allMatch(c -> "0123.".indexOf(c) > -1) || b2i.chars().filter(c -> c == '.').count() > 1) { throw new RuntimeException("Invalid Base 2i number"); } this.b2i = b2i; } public Complex toComplex() { int pointPos = b2i.indexOf("."); int posLen = pointPos != -1 ? pointPos : b2i.length(); Complex sum = new Complex(0, 0); Complex prod = new Complex(1, 0); for (int j = 0; j < posLen; ++j) { double k = b2i.charAt(posLen - 1 - j) - '0'; if (k > 0.0) sum = sum.add(prod.times(k)); prod = prod.times(TWOI); } if (pointPos != -1) { prod = INVTWOI; for (int j = posLen + 1; j < b2i.length(); ++j) { double k = b2i.charAt(j) - '0'; if (k > 0.0) sum = sum.add(prod.times(k)); prod = prod.times(INVTWOI); } } return sum; } @Override public String toString() { return b2i; } } public static void main(String[] args) { String fmt = "%4s -> %8s -> %4s"; for (int i = 1; i <= 16; ++i) { Complex c1 = new Complex(i, 0); QuaterImaginary qi = c1.toQuaterImaginary(); Complex c2 = qi.toComplex(); System.out.printf(fmt + " ", c1, qi, c2); c1 = c2.unaryMinus(); qi = c1.toQuaterImaginary(); c2 = qi.toComplex(); System.out.printf(fmt, c1, qi, c2); System.out.println(); } System.out.println(); for (int i = 1; i <= 16; ++i) { Complex c1 = new Complex(0, i); QuaterImaginary qi = c1.toQuaterImaginary(); Complex c2 = qi.toComplex(); System.out.printf(fmt + " ", c1, qi, c2); c1 = c2.unaryMinus(); qi = c1.toQuaterImaginary(); c2 = qi.toComplex(); System.out.printf(fmt, c1, qi, c2); System.out.println(); } } }
def base2i_decode(qi) return 0 if qi == '0' md = qi.match(/^(?<int>[0-3]+)(?:\.(?<frc>[0-3]+))?$/) raise 'ill-formed quarter-imaginary base value' if !md ls_pow = md[:frc] ? -(md[:frc].length) : 0 value = 0 (md[:int] + (md[:frc] ? md[:frc] : '')).reverse.each_char.with_index do |dig, inx| value += dig.to_i * (2i)**(inx + ls_pow) end return value end def base2i_encode(gi) odd = gi.imag.to_i.odd? frac = (gi.imag.to_i != 0) real = gi.real.to_i imag = (gi.imag.to_i + 1) / 2 value = '' phase_real = true while (real != 0) || (imag != 0) if phase_real real, rem = real.divmod(4) real = -real else imag, rem = imag.divmod(4) imag = -imag end value.prepend(rem.to_s) phase_real = !phase_real end value = '0' if value == '' value.concat(odd ? '.2' : '.0') if frac return value end
Write the same algorithm in Ruby as shown in this Java implementation.
import static java.lang.Math.*; import static java.util.Arrays.stream; import java.util.Locale; import java.util.function.DoubleSupplier; import static java.util.stream.Collectors.joining; import java.util.stream.DoubleStream; import static java.util.stream.IntStream.range; public class Test implements DoubleSupplier { private double mu, sigma; private double[] state = new double[2]; private int index = state.length; Test(double m, double s) { mu = m; sigma = s; } static double[] meanStdDev(double[] numbers) { if (numbers.length == 0) return new double[]{0.0, 0.0}; double sx = 0.0, sxx = 0.0; long n = 0; for (double x : numbers) { sx += x; sxx += pow(x, 2); n++; } return new double[]{sx / n, pow((n * sxx - pow(sx, 2)), 0.5) / n}; } static String replicate(int n, String s) { return range(0, n + 1).mapToObj(i -> s).collect(joining()); } static void showHistogram01(double[] numbers) { final int maxWidth = 50; long[] bins = new long[10]; for (double x : numbers) bins[(int) (x * bins.length)]++; double maxFreq = stream(bins).max().getAsLong(); for (int i = 0; i < bins.length; i++) System.out.printf(" %3.1f: %s%n", i / (double) bins.length, replicate((int) (bins[i] / maxFreq * maxWidth), "*")); System.out.println(); } @Override public double getAsDouble() { index++; if (index >= state.length) { double r = sqrt(-2 * log(random())) * sigma; double x = 2 * PI * random(); state = new double[]{mu + r * sin(x), mu + r * cos(x)}; index = 0; } return state[index]; } public static void main(String[] args) { Locale.setDefault(Locale.US); double[] data = DoubleStream.generate(new Test(0.0, 0.5)).limit(100_000) .toArray(); double[] res = meanStdDev(data); System.out.printf("Mean: %8.6f, SD: %8.6f%n", res[0], res[1]); showHistogram01(stream(data).map(a -> max(0.0, min(0.9999, a / 3 + 0.5))) .toArray()); } }
class NormalFromUniform def initialize() @next = nil end def rand() if @next retval, @next = @next, nil return retval else u = v = s = nil loop do u = Random.rand(-1.0..1.0) v = Random.rand(-1.0..1.0) s = u**2 + v**2 break if (s > 0.0) && (s <= 1.0) end f = Math.sqrt(-2.0 * Math.log(s) / s) @next = v * f return u * f end end end
Write the same algorithm in Ruby as shown in this Java implementation.
import java.util.Arrays; import static java.util.Arrays.stream; import java.util.concurrent.*; public class VogelsApproximationMethod { final static int[] demand = {30, 20, 70, 30, 60}; final static int[] supply = {50, 60, 50, 50}; final static int[][] costs = {{16, 16, 13, 22, 17}, {14, 14, 13, 19, 15}, {19, 19, 20, 23, 50}, {50, 12, 50, 15, 11}}; final static int nRows = supply.length; final static int nCols = demand.length; static boolean[] rowDone = new boolean[nRows]; static boolean[] colDone = new boolean[nCols]; static int[][] result = new int[nRows][nCols]; static ExecutorService es = Executors.newFixedThreadPool(2); public static void main(String[] args) throws Exception { int supplyLeft = stream(supply).sum(); int totalCost = 0; while (supplyLeft > 0) { int[] cell = nextCell(); int r = cell[0]; int c = cell[1]; int quantity = Math.min(demand[c], supply[r]); demand[c] -= quantity; if (demand[c] == 0) colDone[c] = true; supply[r] -= quantity; if (supply[r] == 0) rowDone[r] = true; result[r][c] = quantity; supplyLeft -= quantity; totalCost += quantity * costs[r][c]; } stream(result).forEach(a -> System.out.println(Arrays.toString(a))); System.out.println("Total cost: " + totalCost); es.shutdown(); } static int[] nextCell() throws Exception { Future<int[]> f1 = es.submit(() -> maxPenalty(nRows, nCols, true)); Future<int[]> f2 = es.submit(() -> maxPenalty(nCols, nRows, false)); int[] res1 = f1.get(); int[] res2 = f2.get(); if (res1[3] == res2[3]) return res1[2] < res2[2] ? res1 : res2; return (res1[3] > res2[3]) ? res2 : res1; } static int[] diff(int j, int len, boolean isRow) { int min1 = Integer.MAX_VALUE, min2 = Integer.MAX_VALUE; int minP = -1; for (int i = 0; i < len; i++) { if (isRow ? colDone[i] : rowDone[i]) continue; int c = isRow ? costs[j][i] : costs[i][j]; if (c < min1) { min2 = min1; min1 = c; minP = i; } else if (c < min2) min2 = c; } return new int[]{min2 - min1, min1, minP}; } static int[] maxPenalty(int len1, int len2, boolean isRow) { int md = Integer.MIN_VALUE; int pc = -1, pm = -1, mc = -1; for (int i = 0; i < len1; i++) { if (isRow ? rowDone[i] : colDone[i]) continue; int[] res = diff(i, len2, isRow); if (res[0] > md) { md = res[0]; pm = i; mc = res[1]; pc = res[2]; } } return isRow ? new int[]{pm, pc, mc, md} : new int[]{pc, pm, mc, md}; } }
COSTS = {W: {A: 16, B: 16, C: 13, D: 22, E: 17}, X: {A: 14, B: 14, C: 13, D: 19, E: 15}, Y: {A: 19, B: 19, C: 20, D: 23, E: 50}, Z: {A: 50, B: 12, C: 50, D: 15, E: 11}} demand = {A: 30, B: 20, C: 70, D: 30, E: 60} supply = {W: 50, X: 60, Y: 50, Z: 50} COLS = demand.keys res = {}; COSTS.each_key{|k| res[k] = Hash.new(0)} g = {}; supply.each_key{|x| g[x] = COSTS[x].keys.sort_by{|g| COSTS[x][g]}} demand.each_key{|x| g[x] = COSTS.keys.sort_by{|g| COSTS[g][x]}} until g.empty? d = demand.collect{|x,y| [x, z = COSTS[g[x][0]][x], g[x][1] ? COSTS[g[x][1]][x] - z : z]} dmax = d.max_by{|n| n[2]} d = d.select{|x| x[2] == dmax[2]}.min_by{|n| n[1]} s = supply.collect{|x,y| [x, z = COSTS[x][g[x][0]], g[x][1] ? COSTS[x][g[x][1]] - z : z]} dmax = s.max_by{|n| n[2]} s = s.select{|x| x[2] == dmax[2]}.min_by{|n| n[1]} t,f = d[2]==s[2] ? [s[1], d[1]] : [d[2],s[2]] d,s = t > f ? [d[0],g[d[0]][0]] : [g[s[0]][0],s[0]] v = [supply[s], demand[d]].min res[s][d] += v demand[d] -= v if demand[d] == 0 then supply.reject{|k, n| n == 0}.each_key{|x| g[x].delete(d)} g.delete(d) demand.delete(d) end supply[s] -= v if supply[s] == 0 then demand.reject{|k, n| n == 0}.each_key{|x| g[x].delete(s)} g.delete(s) supply.delete(s) end end COLS.each{|n| print "\t", n} puts cost = 0 COSTS.each_key do |g| print g, "\t" COLS.each do |n| y = res[g][n] print y if y != 0 cost += y * COSTS[g][n] print "\t" end puts end print "\n\nTotal Cost = ", cost
Write a version of this Java function in Ruby with identical behavior.
import java.math.BigInteger; import java.util.ArrayList; import java.util.List; public class MinimumNumberOnlyZeroAndOne { public static void main(String[] args) { for ( int n : getTestCases() ) { BigInteger result = getA004290(n); System.out.printf("A004290(%d) = %s = %s * %s%n", n, result, n, result.divide(BigInteger.valueOf(n))); } } private static List<Integer> getTestCases() { List<Integer> testCases = new ArrayList<>(); for ( int i = 1 ; i <= 10 ; i++ ) { testCases.add(i); } for ( int i = 95 ; i <= 105 ; i++ ) { testCases.add(i); } for (int i : new int[] {297, 576, 594, 891, 909, 999, 1998, 2079, 2251, 2277, 2439, 2997, 4878} ) { testCases.add(i); } return testCases; } private static BigInteger getA004290(int n) { if ( n == 1 ) { return BigInteger.valueOf(1); } int[][] L = new int[n][n]; for ( int i = 2 ; i < n ; i++ ) { L[0][i] = 0; } L[0][0] = 1; L[0][1] = 1; int m = 0; BigInteger ten = BigInteger.valueOf(10); BigInteger nBi = BigInteger.valueOf(n); while ( true ) { m++; if ( L[m-1][mod(ten.pow(m).negate(), nBi).intValue()] == 1 ) { break; } L[m][0] = 1; for ( int k = 1 ; k < n ; k++ ) { L[m][k] = Math.max(L[m-1][k], L[m-1][mod(BigInteger.valueOf(k).subtract(ten.pow(m)), nBi).intValue()]); } } BigInteger r = ten.pow(m); BigInteger k = mod(r.negate(), nBi); for ( int j = m-1 ; j >= 1 ; j-- ) { if ( L[j-1][k.intValue()] == 0 ) { r = r.add(ten.pow(j)); k = mod(k.subtract(ten.pow(j)), nBi); } } if ( k.compareTo(BigInteger.ONE) == 0 ) { r = r.add(BigInteger.ONE); } return r; } private static BigInteger mod(BigInteger m, BigInteger n) { BigInteger result = m.mod(n); if ( result.compareTo(BigInteger.ZERO) < 0 ) { result = result.add(n); } return result; } @SuppressWarnings("unused") private static int mod(int m, int n) { int result = m % n; if ( result < 0 ) { result += n; } return result; } @SuppressWarnings("unused") private static int pow(int base, int exp) { return (int) Math.pow(base, exp); } }
def mod(m, n) result = m % n if result < 0 then result = result + n end return result end def getA004290(n) if n == 1 then return 1 end arr = Array.new(n) { Array.new(n, 0) } arr[0][0] = 1 arr[0][1] = 1 m = 0 while true m = m + 1 if arr[m - 1][mod(-10 ** m, n)] == 1 then break end arr[m][0] = 1 for k in 1 .. n - 1 arr[m][k] = [arr[m - 1][k], arr[m - 1][mod(k - 10 ** m, n)]].max end end r = 10 ** m k = mod(-r, n) (m - 1).downto(1) { |j| if arr[j - 1][k] == 0 then r = r + 10 ** j k = mod(k - 10 ** j, n) end } if k == 1 then r = r + 1 end return r end testCases = Array(1 .. 10) testCases.concat(Array(95 .. 105)) testCases.concat([297, 576, 594, 891, 909, 999, 1998, 2079, 2251, 2277, 2439, 2997, 4878]) for n in testCases result = getA004290(n) print "A004290(%d) = %d = %d * %d\n" % [n, result, n, result / n] end
Produce a language-to-language conversion: from Java to Ruby, same semantics.
public class MagicSquareSinglyEven { public static void main(String[] args) { int n = 6; for (int[] row : magicSquareSinglyEven(n)) { for (int x : row) System.out.printf("%2s ", x); System.out.println(); } System.out.printf("\nMagic constant: %d ", (n * n + 1) * n / 2); } public static int[][] magicSquareOdd(final int n) { if (n < 3 || n % 2 == 0) throw new IllegalArgumentException("base must be odd and > 2"); int value = 0; int gridSize = n * n; int c = n / 2, r = 0; int[][] result = new int[n][n]; while (++value <= gridSize) { result[r][c] = value; if (r == 0) { if (c == n - 1) { r++; } else { r = n - 1; c++; } } else if (c == n - 1) { r--; c = 0; } else if (result[r - 1][c + 1] == 0) { r--; c++; } else { r++; } } return result; } static int[][] magicSquareSinglyEven(final int n) { if (n < 6 || (n - 2) % 4 != 0) throw new IllegalArgumentException("base must be a positive " + "multiple of 4 plus 2"); int size = n * n; int halfN = n / 2; int subSquareSize = size / 4; int[][] subSquare = magicSquareOdd(halfN); int[] quadrantFactors = {0, 2, 3, 1}; int[][] result = new int[n][n]; for (int r = 0; r < n; r++) { for (int c = 0; c < n; c++) { int quadrant = (r / halfN) * 2 + (c / halfN); result[r][c] = subSquare[r % halfN][c % halfN]; result[r][c] += quadrantFactors[quadrant] * subSquareSize; } } int nColsLeft = halfN / 2; int nColsRight = nColsLeft - 1; for (int r = 0; r < halfN; r++) for (int c = 0; c < n; c++) { if (c < nColsLeft || c >= n - nColsRight || (c == nColsLeft && r == nColsLeft)) { if (c == 0 && r == nColsLeft) continue; int tmp = result[r][c]; result[r][c] = result[r + halfN][c]; result[r + halfN][c] = tmp; } } return result; } }
def odd_magic_square(n) n.times.map{|i| n.times.map{|j| n*((i+j+1+n/2)%n) + ((i+2*j-5)%n) + 1} } end def single_even_magic_square(n) raise ArgumentError, "must be even, but not divisible by 4." unless (n-2) % 4 == 0 raise ArgumentError, "2x2 magic square not possible." if n == 2 order = (n-2)/4 odd_square = odd_magic_square(n/2) to_add = (0..3).map{|f| f*n*n/4} quarts = to_add.map{|f| odd_square.dup.map{|row|row.map{|el| el+f}} } sq = [] quarts[0].zip(quarts[2]){|d1,d2| sq << [d1,d2].flatten} quarts[3].zip(quarts[1]){|d1,d2| sq << [d1,d2].flatten} sq = sq.transpose order.times{|i| sq[i].rotate!(n/2)} swap(sq[0][order], sq[0][-order-1]) swap(sq[order][order], sq[order][-order-1]) (order-1).times{|i| sq[-(i+1)].rotate!(n/2)} randomize(sq) end def swap(a,b) a,b = b,a end def randomize(square) square.shuffle.transpose.shuffle end def to_string(square) n = square.size fmt = "% square.inject(""){|str,row| str << fmt % row << "\n"} end puts to_string(single_even_magic_square(6))
Generate a Ruby translation of this Java snippet without changing its computational steps.
import java.util.ArrayList; import java.util.List; public class WeirdNumbers { public static void main(String[] args) { int n = 2; for ( int count = 1 ; count <= 25 ; n += 2 ) { if ( isWeird(n) ) { System.out.printf("w(%d) = %d%n", count, n); count++; } } } private static boolean isWeird(int n) { List<Integer> properDivisors = getProperDivisors(n); return isAbundant(properDivisors, n) && ! isSemiPerfect(properDivisors, n); } private static boolean isAbundant(List<Integer> divisors, int n) { int divisorSum = divisors.stream().mapToInt(i -> i.intValue()).sum(); return divisorSum > n; } private static boolean isSemiPerfect(List<Integer> divisors, int sum) { int size = divisors.size(); boolean subset[][] = new boolean[sum+1][size+1]; for (int i = 0; i <= size; i++) { subset[0][i] = true; } for (int i = 1; i <= sum; i++) { subset[i][0] = false; } for ( int i = 1 ; i <= sum ; i++ ) { for ( int j = 1 ; j <= size ; j++ ) { subset[i][j] = subset[i][j-1]; int test = divisors.get(j-1); if ( i >= test ) { subset[i][j] = subset[i][j] || subset[i - test][j-1]; } } } return subset[sum][size]; } private static final List<Integer> getProperDivisors(int number) { List<Integer> divisors = new ArrayList<Integer>(); long sqrt = (long) Math.sqrt(number); for ( int i = 1 ; i <= sqrt ; i++ ) { if ( number % i == 0 ) { divisors.add(i); int div = number / i; if ( div != i && div != number ) { divisors.add(div); } } } return divisors; } }
def divisors(n : Int32) : Array(Int32) divs = [1] divs2 = [] of Int32 i = 2 while i * i < n if n % i == 0 j = n // i divs << i divs2 << j if i != j end i += 1 end i = divs.size - 1 while i >= 0 divs2 << divs[i] i -= 1 end divs2 end def abundant(n : Int32, divs : Array(Int32)) : Bool divs.sum > n end def semiperfect(n : Int32, divs : Array(Int32)) : Bool if divs.size > 0 h = divs[0] t = divs[1..] return n < h ? semiperfect(n, t) : n == h || semiperfect(n - h, t) || semiperfect(n, t) end return false end def sieve(limit : Int32) : Array(Bool) w = Array(Bool).new(limit, false) i = 2 while i < limit if !w[i] divs = divisors i if !abundant(i, divs) w[i] = true elsif semiperfect(i, divs) j = i while j < limit w[j] = true j += i end end end i += 2 end w end def main w = sieve 17000 count = 0 max = 25 print "The first 25 weird numbers are: " n = 2 while count < max if !w[n] print " count += 1 end n += 2 end puts "\n" end require "benchmark" puts Benchmark.measure { main }
Rewrite the snippet below in Ruby so it works the same as the original Java code.
import java.math.BigInteger; import java.util.ArrayList; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; public class AsciiArtDiagramConverter { private static final String TEST = "+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+\r\n" + "| ID |\r\n" + "+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+\r\n" + "|QR| Opcode |AA|TC|RD|RA| Z | RCODE |\r\n" + "+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+\r\n" + "| QDCOUNT |\r\n" + "+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+\r\n" + "| ANCOUNT |\r\n" + "+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+\r\n" + "| NSCOUNT |\r\n" + "+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+\r\n" + "| ARCOUNT |\r\n" + "+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+"; public static void main(String[] args) { validate(TEST); display(TEST); Map<String,List<Integer>> asciiMap = decode(TEST); displayMap(asciiMap); displayCode(asciiMap, "78477bbf5496e12e1bf169a4"); } private static void displayCode(Map<String,List<Integer>> asciiMap, String hex) { System.out.printf("%nTest string in hex:%n%s%n%n", hex); String bin = new BigInteger(hex,16).toString(2); int length = 0; for ( String code : asciiMap.keySet() ) { List<Integer> pos = asciiMap.get(code); length += pos.get(1) - pos.get(0) + 1; } while ( length > bin.length() ) { bin = "0" + bin; } System.out.printf("Test string in binary:%n%s%n%n", bin); System.out.printf("Name Size Bit Pattern%n"); System.out.printf("-------- ----- -----------%n"); for ( String code : asciiMap.keySet() ) { List<Integer> pos = asciiMap.get(code); int start = pos.get(0); int end = pos.get(1); System.out.printf("%-8s %2d %s%n", code, end-start+1, bin.substring(start, end+1)); } } private static void display(String ascii) { System.out.printf("%nDiagram:%n%n"); for ( String s : TEST.split("\\r\\n") ) { System.out.println(s); } } private static void displayMap(Map<String,List<Integer>> asciiMap) { System.out.printf("%nDecode:%n%n"); System.out.printf("Name Size Start End%n"); System.out.printf("-------- ----- ----- -----%n"); for ( String code : asciiMap.keySet() ) { List<Integer> pos = asciiMap.get(code); System.out.printf("%-8s %2d %2d %2d%n", code, pos.get(1)-pos.get(0)+1, pos.get(0), pos.get(1)); } } private static Map<String,List<Integer>> decode(String ascii) { Map<String,List<Integer>> map = new LinkedHashMap<>(); String[] split = TEST.split("\\r\\n"); int size = split[0].indexOf("+", 1) - split[0].indexOf("+"); int length = split[0].length() - 1; for ( int i = 1 ; i < split.length ; i += 2 ) { int barIndex = 1; String test = split[i]; int next; while ( barIndex < length && (next = test.indexOf("|", barIndex)) > 0 ) { List<Integer> startEnd = new ArrayList<>(); startEnd.add((barIndex/size) + (i/2)*(length/size)); startEnd.add(((next-1)/size) + (i/2)*(length/size)); String code = test.substring(barIndex, next).replace(" ", ""); map.put(code, startEnd); barIndex = next + 1; } } return map; } private static void validate(String ascii) { String[] split = TEST.split("\\r\\n"); if ( split.length % 2 != 1 ) { throw new RuntimeException("ERROR 1: Invalid number of input lines. Line count = " + split.length); } int size = 0; for ( int i = 0 ; i < split.length ; i++ ) { String test = split[i]; if ( i % 2 == 0 ) { if ( ! test.matches("^\\+([-]+\\+)+$") ) { throw new RuntimeException("ERROR 2: Improper line format. Line = " + test); } if ( size == 0 ) { int firstPlus = test.indexOf("+"); int secondPlus = test.indexOf("+", 1); size = secondPlus - firstPlus; } if ( ((test.length()-1) % size) != 0 ) { throw new RuntimeException("ERROR 3: Improper line format. Line = " + test); } for ( int j = 0 ; j < test.length()-1 ; j += size ) { if ( test.charAt(j) != '+' ) { throw new RuntimeException("ERROR 4: Improper line format. Line = " + test); } for ( int k = j+1 ; k < j + size ; k++ ) { if ( test.charAt(k) != '-' ) { throw new RuntimeException("ERROR 5: Improper line format. Line = " + test); } } } } else { if ( ! test.matches("^\\|(\\s*[A-Za-z]+\\s*\\|)+$") ) { throw new RuntimeException("ERROR 6: Improper line format. Line = " + test); } for ( int j = 0 ; j < test.length()-1 ; j += size ) { for ( int k = j+1 ; k < j + size ; k++ ) { if ( test.charAt(k) == '|' ) { throw new RuntimeException("ERROR 7: Improper line format. Line = " + test); } } } } } } }
header = <<HEADER +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ | ID | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ |QR| Opcode |AA|TC|RD|RA| Z | RCODE | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ | QDCOUNT | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ | ANCOUNT | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ | NSCOUNT | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ | ARCOUNT | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ HEADER Item = Struct.new(:name, :bits, :range) RE = /\| *\w+ */ i = 0 table = header.scan(RE).map{|m| Item.new( m.delete("^A-Za-z"), b = m.size/3, i...(i += b)) } teststr = "78477bbf5496e12e1bf169a4" padding = table.sum(&:bits) binstr = teststr.hex.to_s(2).rjust(padding, "0") table.each{|el| p el.values}; puts table.each{|el| puts "%7s, %2d bits: %s" % [el.name, el.bits, binstr[el.range] ]}
Produce a functionally identical Ruby code for the snippet given in Java.
import java.util.ArrayList; import java.util.Arrays; import java.util.List; public class Peaceful { enum Piece { Empty, Black, White, } public static class Position { public int x, y; public Position(int x, int y) { this.x = x; this.y = y; } @Override public boolean equals(Object obj) { if (obj instanceof Position) { Position pos = (Position) obj; return pos.x == x && pos.y == y; } return false; } } private static boolean place(int m, int n, List<Position> pBlackQueens, List<Position> pWhiteQueens) { if (m == 0) { return true; } boolean placingBlack = true; for (int i = 0; i < n; ++i) { inner: for (int j = 0; j < n; ++j) { Position pos = new Position(i, j); for (Position queen : pBlackQueens) { if (pos.equals(queen) || !placingBlack && isAttacking(queen, pos)) { continue inner; } } for (Position queen : pWhiteQueens) { if (pos.equals(queen) || placingBlack && isAttacking(queen, pos)) { continue inner; } } if (placingBlack) { pBlackQueens.add(pos); placingBlack = false; } else { pWhiteQueens.add(pos); if (place(m - 1, n, pBlackQueens, pWhiteQueens)) { return true; } pBlackQueens.remove(pBlackQueens.size() - 1); pWhiteQueens.remove(pWhiteQueens.size() - 1); placingBlack = true; } } } if (!placingBlack) { pBlackQueens.remove(pBlackQueens.size() - 1); } return false; } private static boolean isAttacking(Position queen, Position pos) { return queen.x == pos.x || queen.y == pos.y || Math.abs(queen.x - pos.x) == Math.abs(queen.y - pos.y); } private static void printBoard(int n, List<Position> blackQueens, List<Position> whiteQueens) { Piece[] board = new Piece[n * n]; Arrays.fill(board, Piece.Empty); for (Position queen : blackQueens) { board[queen.x + n * queen.y] = Piece.Black; } for (Position queen : whiteQueens) { board[queen.x + n * queen.y] = Piece.White; } for (int i = 0; i < board.length; ++i) { if ((i != 0) && i % n == 0) { System.out.println(); } Piece b = board[i]; if (b == Piece.Black) { System.out.print("B "); } else if (b == Piece.White) { System.out.print("W "); } else { int j = i / n; int k = i - j * n; if (j % 2 == k % 2) { System.out.print("• "); } else { System.out.print("◦ "); } } } System.out.println('\n'); } public static void main(String[] args) { List<Position> nms = List.of( new Position(2, 1), new Position(3, 1), new Position(3, 2), new Position(4, 1), new Position(4, 2), new Position(4, 3), new Position(5, 1), new Position(5, 2), new Position(5, 3), new Position(5, 4), new Position(5, 5), new Position(6, 1), new Position(6, 2), new Position(6, 3), new Position(6, 4), new Position(6, 5), new Position(6, 6), new Position(7, 1), new Position(7, 2), new Position(7, 3), new Position(7, 4), new Position(7, 5), new Position(7, 6), new Position(7, 7) ); for (Position nm : nms) { int m = nm.y; int n = nm.x; System.out.printf("%d black and %d white queens on a %d x %d board:\n", m, m, n, n); List<Position> blackQueens = new ArrayList<>(); List<Position> whiteQueens = new ArrayList<>(); if (place(m, n, blackQueens, whiteQueens)) { printBoard(n, blackQueens, whiteQueens); } else { System.out.println("No solution exists.\n"); } } } }
class Position attr_reader :x, :y def initialize(x, y) @x = x @y = y end def ==(other) self.x == other.x && self.y == other.y end def to_s '(%d, %d)' % [@x, @y] end def to_str to_s end end def isAttacking(queen, pos) return queen.x == pos.x || queen.y == pos.y || (queen.x - pos.x).abs() == (queen.y - pos.y).abs() end def place(m, n, blackQueens, whiteQueens) if m == 0 then return true end placingBlack = true for i in 0 .. n-1 for j in 0 .. n-1 catch :inner do pos = Position.new(i, j) for queen in blackQueens if pos == queen || !placingBlack && isAttacking(queen, pos) then throw :inner end end for queen in whiteQueens if pos == queen || placingBlack && isAttacking(queen, pos) then throw :inner end end if placingBlack then blackQueens << pos placingBlack = false else whiteQueens << pos if place(m - 1, n, blackQueens, whiteQueens) then return true end blackQueens.pop whiteQueens.pop placingBlack = true end end end end if !placingBlack then blackQueens.pop end return false end def printBoard(n, blackQueens, whiteQueens) board = Array.new(n) { Array.new(n) { ' ' } } for i in 0 .. n-1 for j in 0 .. n-1 if i % 2 == j % 2 then board[i][j] = '•' else board[i][j] = '◦' end end end for queen in blackQueens board[queen.y][queen.x] = 'B' end for queen in whiteQueens board[queen.y][queen.x] = 'W' end for row in board for cell in row print cell, ' ' end print "\n" end print "\n" end nms = [ [2, 1], [3, 1], [3, 2], [4, 1], [4, 2], [4, 3], [5, 1], [5, 2], [5, 3], [5, 4], [5, 5], [6, 1], [6, 2], [6, 3], [6, 4], [6, 5], [6, 6], [7, 1], [7, 2], [7, 3], [7, 4], [7, 5], [7, 6], [7, 7] ] for nm in nms m = nm[1] n = nm[0] print "%d black and %d white queens on a %d x %d board:\n" % [m, m, n, n] blackQueens = [] whiteQueens = [] if place(m, n, blackQueens, whiteQueens) then printBoard(n, blackQueens, whiteQueens) else print "No solution exists.\n\n" end end
Change the following Java code into Ruby without altering its purpose.
import java.math.BigInteger; import java.util.ArrayList; import java.util.List; public class SequenceNthNumberWithExactlyNDivisors { public static void main(String[] args) { int max = 45; smallPrimes(max); for ( int n = 1; n <= max ; n++ ) { System.out.printf("A073916(%d) = %s%n", n, OEISA073916(n)); } } private static List<Integer> smallPrimes = new ArrayList<>(); private static void smallPrimes(int numPrimes) { smallPrimes.add(2); for ( int n = 3, count = 0 ; count < numPrimes ; n += 2 ) { if ( isPrime(n) ) { smallPrimes.add(n); count++; } } } private static final boolean isPrime(long test) { if ( test == 2 ) { return true; } if ( test % 2 == 0 ) { return false; } for ( long d = 3 ; d*d <= test ; d += 2 ) { if ( test % d == 0 ) { return false; } } return true; } private static int getDivisorCount(long n) { int count = 1; while ( n % 2 == 0 ) { n /= 2; count += 1; } for ( long d = 3 ; d*d <= n ; d += 2 ) { long q = n / d; long r = n % d; int dc = 0; while ( r == 0 ) { dc += count; n = q; q = n / d; r = n % d; } count += dc; } if ( n != 1 ) { count *= 2; } return count; } private static BigInteger OEISA073916(int n) { if ( isPrime(n) ) { return BigInteger.valueOf(smallPrimes.get(n-1)).pow(n - 1); } int count = 0; int result = 0; for ( int i = 1 ; count < n ; i++ ) { if ( n % 2 == 1 ) { int sqrt = (int) Math.sqrt(i); if ( sqrt*sqrt != i ) { continue; } } if ( getDivisorCount(i) == n ) { count++; result = i; } } return BigInteger.valueOf(result); } }
def isPrime(n) return false if n < 2 return n == 2 if n % 2 == 0 return n == 3 if n % 3 == 0 k = 5 while k * k <= n return false if n % k == 0 k = k + 2 end return true end def getSmallPrimes(numPrimes) smallPrimes = [2] count = 0 n = 3 while count < numPrimes if isPrime(n) then smallPrimes << n count = count + 1 end n = n + 2 end return smallPrimes end def getDivisorCount(n) count = 1 while n % 2 == 0 n = (n / 2).floor count = count + 1 end d = 3 while d * d <= n q = (n / d).floor r = n % d dc = 0 while r == 0 dc = dc + count n = q q = (n / d).floor r = n % d end count = count + dc d = d + 2 end if n != 1 then count = 2 * count end return count end MAX = 15 @smallPrimes = getSmallPrimes(MAX) def OEISA073916(n) if isPrime(n) then return @smallPrimes[n - 1] ** (n - 1) end count = 0 result = 0 i = 1 while count < n if n % 2 == 1 then root = Math.sqrt(i) if root * root != i then i = i + 1 next end end if getDivisorCount(i) == n then count = count + 1 result = i end i = i + 1 end return result end n = 1 while n <= MAX print "A073916(", n, ") = ", OEISA073916(n), "\n" n = n + 1 end
Preserve the algorithm and functionality while converting the code from Java to Ruby.
import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.HashMap; import java.util.LinkedList; import java.util.Map; public class ReadlineInterface { private static LinkedList<String> histArr = new LinkedList<>(); private static void hist() { if (histArr.isEmpty()) { System.out.println("No history"); } else { histArr.forEach(cmd -> System.out.printf(" - %s\n", cmd)); } class Crutch {} histArr.add(Crutch.class.getEnclosingMethod().getName()); } private static void hello() { System.out.println("Hello World!"); class Crutch {} histArr.add(Crutch.class.getEnclosingMethod().getName()); } private static void help() { System.out.println("Available commands:"); System.out.println(" hello"); System.out.println(" hist"); System.out.println(" exit"); System.out.println(" help"); class Crutch {} histArr.add(Crutch.class.getEnclosingMethod().getName()); } public static void main(String[] args) throws IOException { Map<String, Runnable> cmdMap = new HashMap<>(); cmdMap.put("help", ReadlineInterface::help); cmdMap.put("hist", ReadlineInterface::hist); cmdMap.put("hello", ReadlineInterface::hello); BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); System.out.println("Enter a command, type help for a listing."); while (true) { System.out.print(">"); String line = in.readLine(); if ("exit".equals(line)) { break; } cmdMap.getOrDefault(line, ReadlineInterface::help).run(); } } }
require "readline" require "abbrev" commands = %w[search download open help history quit url prev past] Readline.completion_proc = commands.abbrev.to_proc while buf = Readline.readline(">", true) exit if buf.strip == "quit" p buf end
Change the following Java code into Ruby without altering its purpose.
public class AdditionChains { private static class Pair { int f, s; Pair(int f, int s) { this.f = f; this.s = s; } } private static int[] prepend(int n, int[] seq) { int[] result = new int[seq.length + 1]; result[0] = n; System.arraycopy(seq, 0, result, 1, seq.length); return result; } private static Pair check_seq(int pos, int[] seq, int n, int min_len) { if (pos > min_len || seq[0] > n) return new Pair(min_len, 0); else if (seq[0] == n) return new Pair(pos, 1); else if (pos < min_len) return try_perm(0, pos, seq, n, min_len); else return new Pair(min_len, 0); } private static Pair try_perm(int i, int pos, int[] seq, int n, int min_len) { if (i > pos) return new Pair(min_len, 0); Pair res1 = check_seq(pos + 1, prepend(seq[0] + seq[i], seq), n, min_len); Pair res2 = try_perm(i + 1, pos, seq, n, res1.f); if (res2.f < res1.f) return res2; else if (res2.f == res1.f) return new Pair(res2.f, res1.s + res2.s); else throw new RuntimeException("Try_perm exception"); } private static Pair init_try_perm(int x) { return try_perm(0, 0, new int[]{1}, x, 12); } private static void find_brauer(int num) { Pair res = init_try_perm(num); System.out.println(); System.out.println("N = " + num); System.out.println("Minimum length of chains: L(n)= " + res.f); System.out.println("Number of minimum length Brauer chains: " + res.s); } public static void main(String[] args) { int[] nums = new int[]{7, 14, 21, 29, 32, 42, 64, 47, 79, 191, 382, 379}; for (int i : nums) { find_brauer(i); } } }
def check_seq(pos, seq, n, min_len) if pos > min_len or seq[0] > n then return min_len, 0 elsif seq[0] == n then return pos, 1 elsif pos < min_len then return try_perm(0, pos, seq, n, min_len) else return min_len, 0 end end def try_perm(i, pos, seq, n, min_len) if i > pos then return min_len, 0 end res11, res12 = check_seq(pos + 1, [seq[0] + seq[i]] + seq, n, min_len) res21, res22 = try_perm(i + 1, pos, seq, n, res11) if res21 < res11 then return res21, res22 elsif res21 == res11 then return res21, res12 + res22 else raise "try_perm exception" end end def init_try_perm(x) return try_perm(0, 0, [1], x, 12) end def find_brauer(num) actualMin, brauer = init_try_perm(num) puts print "N = ", num, "\n" print "Minimum length of chains: L(n)= ", actualMin, "\n" print "Number of minimum length Brauer chains: ", brauer, "\n" end def main nums = [7, 14, 21, 29, 32, 42, 64, 47, 79, 191, 382, 379] for i in nums do find_brauer(i) end end main()
Ensure the translated Ruby code behaves exactly like the original Java snippet.
import java.math.BigInteger; public class MontgomeryReduction { private static final BigInteger ZERO = BigInteger.ZERO; private static final BigInteger ONE = BigInteger.ONE; private static final BigInteger TWO = BigInteger.valueOf(2); public static class Montgomery { public static final int BASE = 2; BigInteger m; BigInteger rrm; int n; public Montgomery(BigInteger m) { if (m.compareTo(BigInteger.ZERO) <= 0 || !m.testBit(0)) { throw new IllegalArgumentException(); } this.m = m; this.n = m.bitLength(); this.rrm = ONE.shiftLeft(n * 2).mod(m); } public BigInteger reduce(BigInteger t) { BigInteger a = t; for (int i = 0; i < n; i++) { if (a.testBit(0)) a = a.add(this.m); a = a.shiftRight(1); } if (a.compareTo(m) >= 0) a = a.subtract(this.m); return a; } } public static void main(String[] args) { BigInteger m = new BigInteger("750791094644726559640638407699"); BigInteger x1 = new BigInteger("540019781128412936473322405310"); BigInteger x2 = new BigInteger("515692107665463680305819378593"); Montgomery mont = new Montgomery(m); BigInteger t1 = x1.multiply(mont.rrm); BigInteger t2 = x2.multiply(mont.rrm); BigInteger r1 = mont.reduce(t1); BigInteger r2 = mont.reduce(t2); BigInteger r = ONE.shiftLeft(mont.n); System.out.printf("b : %s\n", Montgomery.BASE); System.out.printf("n : %s\n", mont.n); System.out.printf("r : %s\n", r); System.out.printf("m : %s\n", mont.m); System.out.printf("t1: %s\n", t1); System.out.printf("t2: %s\n", t2); System.out.printf("r1: %s\n", r1); System.out.printf("r2: %s\n", r2); System.out.println(); System.out.printf("Original x1  : %s\n", x1); System.out.printf("Recovered from r1 : %s\n", mont.reduce(r1)); System.out.printf("Original x2  : %s\n", x2); System.out.printf("Recovered from r2 : %s\n", mont.reduce(r2)); System.out.println(); System.out.println("Montgomery computation of x1 ^ x2 mod m :"); BigInteger prod = mont.reduce(mont.rrm); BigInteger base = mont.reduce(x1.multiply(mont.rrm)); BigInteger exp = x2; while (exp.bitLength()>0) { if (exp.testBit(0)) prod=mont.reduce(prod.multiply(base)); exp = exp.shiftRight(1); base = mont.reduce(base.multiply(base)); } System.out.println(mont.reduce(prod)); System.out.println(); System.out.println("Library-based computation of x1 ^ x2 mod m :"); System.out.println(x1.modPow(x2, m)); } }
func montgomeryReduce(m, a) { { a += m if a.is_odd a >>= 1 } * m.as_bin.len a % m } var m = 750791094644726559640638407699 var t1 = 323165824550862327179367294465482435542970161392400401329100 var r1 = 440160025148131680164261562101 var r2 = 435362628198191204145287283255 var x1 = 540019781128412936473322405310 var x2 = 515692107665463680305819378593 say("Original x1: ", x1) say("Recovererd from r1: ", montgomeryReduce(m, r1)) say("Original x2: ", x2) say("Recovererd from r2: ", montgomeryReduce(m, r2)) print("\nMontgomery computation of x1^x2 mod m: ") var prod = montgomeryReduce(m, t1/x1) var base = montgomeryReduce(m, t1) for (var exponent = x2; exponent ; exponent >>= 1) { prod = montgomeryReduce(m, prod * base) if exponent.is_odd base = montgomeryReduce(m, base * base) } say(montgomeryReduce(m, prod)) say("Library-based computation of x1^x2 mod m: ", x1.powmod(x2, m))