repo stringclasses 1k
values | file_url stringlengths 96 373 | file_path stringlengths 11 294 | content stringlengths 0 32.8k | language stringclasses 1
value | license stringclasses 6
values | commit_sha stringclasses 1k
values | retrieved_at stringdate 2026-01-04 14:45:56 2026-01-04 18:30:23 | truncated bool 2
classes |
|---|---|---|---|---|---|---|---|---|
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/permutation/StringPermutation.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/permutation/StringPermutation.java | package com.baeldung.algorithms.permutation;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
public class StringPermutation {
public static boolean isPermutationWithSorting(String s1, String s2) {
if (s1.length() != s2.length()) {
return false;
}
char[] s1CharArray = s1.toCharArray();
char[] s2CharArray = s2.toCharArray();
Arrays.sort(s1CharArray);
Arrays.sort(s2CharArray);
return Arrays.equals(s1CharArray, s2CharArray);
}
public static boolean isPermutationWithOneCounter(String s1, String s2) {
if (s1.length() != s2.length()) {
return false;
}
int[] counter = new int[256];
for (int i = 0; i < s1.length(); i++) {
counter[s1.charAt(i)]++;
counter[s2.charAt(i)]--;
}
for (int count : counter) {
if (count != 0) {
return false;
}
}
return true;
}
public static boolean isPermutationWithTwoCounters(String s1, String s2) {
if (s1.length() != s2.length()) {
return false;
}
int[] counter1 = new int[256];
int[] counter2 = new int[256];
for (int i = 0; i < s1.length(); i++) {
counter1[s1.charAt(i)]++;
}
for (int i = 0; i < s2.length(); i++) {
counter2[s2.charAt(i)]++;
}
return Arrays.equals(counter1, counter2);
}
public static boolean isPermutationWithMap(String s1, String s2) {
if (s1.length() != s2.length()) {
return false;
}
Map<Character, Integer> charsMap = new HashMap<>();
for (int i = 0; i < s1.length(); i++) {
charsMap.merge(s1.charAt(i), 1, Integer::sum);
}
for (int i = 0; i < s2.length(); i++) {
if (!charsMap.containsKey(s2.charAt(i)) || charsMap.get(s2.charAt(i)) == 0) {
return false;
}
charsMap.merge(s2.charAt(i), -1, Integer::sum);
}
return true;
}
public static boolean isPermutationInclusion(String s1, String s2) {
int ns1 = s1.length(), ns2 = s2.length();
if (ns1 < ns2) {
return false;
}
int[] s1Count = new int[26];
int[] s2Count = new int[26];
for (char ch : s2.toCharArray()) {
s2Count[ch - 'a']++;
}
for (int i = 0; i < ns1; ++i) {
s1Count[s1.charAt(i) - 'a']++;
if (i >= ns2) {
s1Count[s1.charAt(i - ns2) - 'a']--;
}
if (Arrays.equals(s2Count, s1Count)) {
return true;
}
}
return false;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/minimax/Node.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/minimax/Node.java | package com.baeldung.algorithms.minimax;
import java.util.ArrayList;
import java.util.List;
public class Node {
private int noOfBones;
private boolean isMaxPlayer;
private int score;
private List<Node> children;
public Node(int noOfBones, boolean isMaxPlayer) {
this.noOfBones = noOfBones;
this.isMaxPlayer = isMaxPlayer;
children = new ArrayList<>();
}
int getNoOfBones() {
return noOfBones;
}
boolean isMaxPlayer() {
return isMaxPlayer;
}
int getScore() {
return score;
}
void setScore(int score) {
this.score = score;
}
List<Node> getChildren() {
return children;
}
void addChild(Node newNode) {
children.add(newNode);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/minimax/Tree.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/minimax/Tree.java | package com.baeldung.algorithms.minimax;
public class Tree {
private Node root;
Tree() {
}
Node getRoot() {
return root;
}
void setRoot(Node root) {
this.root = root;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/minimax/GameOfBones.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/minimax/GameOfBones.java | package com.baeldung.algorithms.minimax;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
class GameOfBones {
static List<Integer> getPossibleStates(int noOfBonesInHeap) {
return IntStream.rangeClosed(1, 3).boxed()
.map(i -> noOfBonesInHeap - i)
.filter(newHeapCount -> newHeapCount >= 0)
.collect(Collectors.toList());
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/minimax/MiniMax.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/minimax/MiniMax.java | package com.baeldung.algorithms.minimax;
import java.util.Comparator;
import java.util.List;
import java.util.NoSuchElementException;
public class MiniMax {
private Tree tree;
public Tree getTree() {
return tree;
}
public void constructTree(int noOfBones) {
tree = new Tree();
Node root = new Node(noOfBones, true);
tree.setRoot(root);
constructTree(root);
}
private void constructTree(Node parentNode) {
List<Integer> listofPossibleHeaps = GameOfBones.getPossibleStates(parentNode.getNoOfBones());
boolean isChildMaxPlayer = !parentNode.isMaxPlayer();
listofPossibleHeaps.forEach(n -> {
Node newNode = new Node(n, isChildMaxPlayer);
parentNode.addChild(newNode);
if (newNode.getNoOfBones() > 0) {
constructTree(newNode);
}
});
}
public boolean checkWin() {
Node root = tree.getRoot();
checkWin(root);
return root.getScore() == 1;
}
private void checkWin(Node node) {
List<Node> children = node.getChildren();
boolean isMaxPlayer = node.isMaxPlayer();
children.forEach(child -> {
if (child.getNoOfBones() == 0) {
child.setScore(isMaxPlayer ? 1 : -1);
} else {
checkWin(child);
}
});
Node bestChild = findBestChild(isMaxPlayer, children);
node.setScore(bestChild.getScore());
}
private Node findBestChild(boolean isMaxPlayer, List<Node> children) {
Comparator<Node> byScoreComparator = Comparator.comparing(Node::getScore);
return children.stream()
.max(isMaxPlayer ? byScoreComparator : byScoreComparator.reversed())
.orElseThrow(NoSuchElementException::new);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/kthlargest/FindKthLargest.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/kthlargest/FindKthLargest.java | package com.baeldung.algorithms.kthlargest;
import java.util.Arrays;
import java.util.Collections;
import java.util.stream.IntStream;
public class FindKthLargest {
public int findKthLargestBySorting(Integer[] arr, int k) {
Arrays.sort(arr);
int targetIndex = arr.length - k;
return arr[targetIndex];
}
public int findSecondLargestWithoutSorting(Integer[] arr) throws Exception{
Integer[] result = new Integer[2];
if (arr == null || arr.length < 2) {
throw new Exception(
"Array should have at least two elements and be not null");
} else {
if (arr[0] > arr[1]) {
result[0] = arr[0];
result[1] = arr[1];
} else {
result[0] = arr[1];
result[1] = arr[0];
}
if (arr.length > 2) {
for (int i = 2; i < arr.length; i++) {
if (arr[i] > result[0]) {
result[1] = result[0];
result[0] = arr[i];
} else if (arr[i] > result[1]) {
result[1] = arr[i];
}
}
}
}
return result[1];
}
public int findKthLargestBySortingDesc(Integer[] arr, int k) {
Arrays.sort(arr, Collections.reverseOrder());
return arr[k - 1];
}
public int findKthElementByQuickSelect(Integer[] arr, int left, int right, int k) {
if (k >= 0 && k <= right - left + 1) {
int pos = partition(arr, left, right);
if (pos - left == k) {
return arr[pos];
}
if (pos - left > k) {
return findKthElementByQuickSelect(arr, left, pos - 1, k);
}
return findKthElementByQuickSelect(arr, pos + 1, right, k - pos + left - 1);
}
return 0;
}
public int findKthElementByQuickSelectWithIterativePartition(Integer[] arr, int left, int right, int k) {
if (k >= 0 && k <= right - left + 1) {
int pos = partitionIterative(arr, left, right);
if (pos - left == k) {
return arr[pos];
}
if (pos - left > k) {
return findKthElementByQuickSelectWithIterativePartition(arr, left, pos - 1, k);
}
return findKthElementByQuickSelectWithIterativePartition(arr, pos + 1, right, k - pos + left - 1);
}
return 0;
}
private int partition(Integer[] arr, int left, int right) {
int pivot = arr[right];
Integer[] leftArr;
Integer[] rightArr;
leftArr = IntStream.range(left, right)
.filter(i -> arr[i] < pivot)
.map(i -> arr[i])
.boxed()
.toArray(Integer[]::new);
rightArr = IntStream.range(left, right)
.filter(i -> arr[i] > pivot)
.map(i -> arr[i])
.boxed()
.toArray(Integer[]::new);
int leftArraySize = leftArr.length;
System.arraycopy(leftArr, 0, arr, left, leftArraySize);
arr[leftArraySize + left] = pivot;
System.arraycopy(rightArr, 0, arr, left + leftArraySize + 1, rightArr.length);
return left + leftArraySize;
}
private int partitionIterative(Integer[] arr, int left, int right) {
int pivot = arr[right], i = left;
for (int j = left; j <= right - 1; j++) {
if (arr[j] <= pivot) {
swap(arr, i, j);
i++;
}
}
swap(arr, i, right);
return i;
}
public int findKthElementByRandomizedQuickSelect(Integer[] arr, int left, int right, int k) {
if (k >= 0 && k <= right - left + 1) {
int pos = randomPartition(arr, left, right);
if (pos - left == k) {
return arr[pos];
}
if (pos - left > k) {
return findKthElementByRandomizedQuickSelect(arr, left, pos - 1, k);
}
return findKthElementByRandomizedQuickSelect(arr, pos + 1, right, k - pos + left - 1);
}
return 0;
}
private int randomPartition(Integer arr[], int left, int right) {
int n = right - left + 1;
int pivot = (int) (Math.random() * n);
swap(arr, left + pivot, right);
return partition(arr, left, right);
}
private void swap(Integer[] arr, int n1, int n2) {
int temp = arr[n2];
arr[n2] = arr[n1];
arr[n1] = temp;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/successivepairs/SuccessivePairs.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/successivepairs/SuccessivePairs.java | package com.baeldung.algorithms.successivepairs;
import java.util.AbstractMap.SimpleEntry;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import java.util.stream.Stream;
public class SuccessivePairs {
public static <T> List<SimpleEntry<T, T>> collectSuccessivePairs(Stream<T> stream) {
List<T> list = stream.collect(Collectors.toList());
return IntStream.range(0, list.size() - 1)
.mapToObj(i -> new SimpleEntry<>(list.get(i), list.get(i + 1)))
.collect(Collectors.toList());
}
public static <T> Stream<List<T>> pairwise(Stream<T> stream) {
List<T> list = stream.collect(Collectors.toList());
List<List<T>> pairs = new ArrayList<>();
for (int i = 0; i < list.size() - 1; i++) {
pairs.add(Arrays.asList(list.get(i), list.get(i + 1)));
}
return pairs.stream();
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/countoccurence/CountOccurrence.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/countoccurence/CountOccurrence.java | package com.baeldung.algorithms.countoccurence;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.function.Function;
import java.util.stream.Collectors;
public class CountOccurrence {
public static int[] countOccurrencesWithCounter(int[] elements, int n) {
int[] counter = new int[n];
for (int element : elements) {
counter[element]++;
}
return counter;
}
public static <T> Map<T, Integer> countOccurrencesWithMap(T[] elements) {
Map<T, Integer> counter = new HashMap<>();
for (T element : elements) {
counter.merge(element, 1, Integer::sum);
}
return counter;
}
public static <T> Map<T, Long> countOccurrencesWithStream(T[] elements) {
return Arrays.stream(elements)
.collect(Collectors.groupingBy(Function.identity(), Collectors.counting()));
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/subarray/SubarrayMeansBruteForce.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/subarray/SubarrayMeansBruteForce.java | package com.baeldung.algorithms.subarray;
public class SubarrayMeansBruteForce {
public static int countSubarraysWithMean(int[] inputArray, int mean) {
int count = 0;
for (int i = 0; i < inputArray.length; i++) {
long sum = 0;
for (int j = i; j < inputArray.length; j++) {
sum += inputArray[j];
if (sum * 1.0 / (j - i + 1) == mean) {
count++;
}
}
}
return count;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/subarray/SubarrayMeansPrefixSums.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/subarray/SubarrayMeansPrefixSums.java | package com.baeldung.algorithms.subarray;
import java.util.HashMap;
import java.util.Map;
public class SubarrayMeansPrefixSums {
public static int countSubarraysWithMean(int[] inputArray, int mean) {
int n = inputArray.length;
long[] prefixSums = new long[n + 1];
long[] adjustedPrefixes = new long[n + 1];
for (int i = 0; i < n; i++) {
prefixSums[i + 1] = prefixSums[i] + inputArray[i];
adjustedPrefixes[i + 1] = prefixSums[i + 1] - (long) mean * (i + 1);
}
Map<Long, Integer> count = new HashMap<>();
int total = 0;
for (long adjustedPrefix : adjustedPrefixes) {
total += count.getOrDefault(adjustedPrefix, 0);
count.put(adjustedPrefix, count.getOrDefault(adjustedPrefix, 0) + 1);
}
return total;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/editdistance/EditDistanceDynamicProgramming.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/editdistance/EditDistanceDynamicProgramming.java | package com.baeldung.algorithms.editdistance;
public class EditDistanceDynamicProgramming extends EditDistanceBase {
static int calculate(String x, String y) {
int[][] dp = new int[x.length() + 1][y.length() + 1];
for (int i = 0; i <= x.length(); i++) {
for (int j = 0; j <= y.length(); j++) {
if (i == 0)
dp[i][j] = j;
else if (j == 0)
dp[i][j] = i;
else {
dp[i][j] = min(dp[i - 1][j - 1]
+ costOfSubstitution(x.charAt(i - 1), y.charAt(j - 1)),
dp[i - 1][j] + 1, dp[i][j - 1] + 1);
}
}
}
return dp[x.length()][y.length()];
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/editdistance/EditDistanceBase.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/editdistance/EditDistanceBase.java | package com.baeldung.algorithms.editdistance;
import java.util.Arrays;
public class EditDistanceBase {
static int costOfSubstitution(char a, char b) {
return a == b ? 0 : 1;
}
static int min(int... numbers) {
return Arrays.stream(numbers)
.min().orElse(Integer.MAX_VALUE);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/editdistance/EditDistanceRecursive.java | algorithms-modules/algorithms-miscellaneous-9/src/main/java/com/baeldung/algorithms/editdistance/EditDistanceRecursive.java | package com.baeldung.algorithms.editdistance;
public class EditDistanceRecursive extends EditDistanceBase {
static int calculate(String x, String y) {
if (x.isEmpty()) {
return y.length();
}
if (y.isEmpty()) {
return x.length();
}
int substitution = calculate(x.substring(1), y.substring(1)) + costOfSubstitution(x.charAt(0), y.charAt(0));
int insertion = calculate(x, y.substring(1)) + 1;
int deletion = calculate(x.substring(1), y) + 1;
return min(substitution, insertion, deletion);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/dijkstra/DijkstraAlgorithmLongRunningUnitTest.java | algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/dijkstra/DijkstraAlgorithmLongRunningUnitTest.java | package com.baeldung.algorithms.dijkstra;
import static org.junit.Assert.assertTrue;
import java.util.Arrays;
import java.util.List;
import org.junit.jupiter.api.Test;
import com.baeldung.algorithms.dijkstra.Dijkstra;
import com.baeldung.algorithms.dijkstra.Graph;
import com.baeldung.algorithms.dijkstra.Node;
class DijkstraAlgorithmLongRunningUnitTest {
@Test
public void whenSPPSolved_thenCorrect() {
Node nodeA = new Node("A");
Node nodeB = new Node("B");
Node nodeC = new Node("C");
Node nodeD = new Node("D");
Node nodeE = new Node("E");
Node nodeF = new Node("F");
nodeA.addDestination(nodeB, 10);
nodeA.addDestination(nodeC, 15);
nodeB.addDestination(nodeD, 12);
nodeB.addDestination(nodeF, 15);
nodeC.addDestination(nodeE, 10);
nodeD.addDestination(nodeE, 2);
nodeD.addDestination(nodeF, 1);
nodeF.addDestination(nodeE, 5);
Graph graph = new Graph();
graph.addNode(nodeA);
graph.addNode(nodeB);
graph.addNode(nodeC);
graph.addNode(nodeD);
graph.addNode(nodeE);
graph.addNode(nodeF);
graph = Dijkstra.calculateShortestPathFromSource(graph, nodeA);
List<Node> shortestPathForNodeB = Arrays.asList(nodeA);
List<Node> shortestPathForNodeC = Arrays.asList(nodeA);
List<Node> shortestPathForNodeD = Arrays.asList(nodeA, nodeB);
List<Node> shortestPathForNodeE = Arrays.asList(nodeA, nodeB, nodeD);
List<Node> shortestPathForNodeF = Arrays.asList(nodeA, nodeB, nodeD);
for (Node node : graph.getNodes()) {
switch (node.getName()) {
case "B":
assertTrue(node
.getShortestPath()
.equals(shortestPathForNodeB));
break;
case "C":
assertTrue(node
.getShortestPath()
.equals(shortestPathForNodeC));
break;
case "D":
assertTrue(node
.getShortestPath()
.equals(shortestPathForNodeD));
break;
case "E":
assertTrue(node
.getShortestPath()
.equals(shortestPathForNodeE));
break;
case "F":
assertTrue(node
.getShortestPath()
.equals(shortestPathForNodeF));
break;
}
}
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/enumstatemachine/LeaveRequestStateUnitTest.java | algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/enumstatemachine/LeaveRequestStateUnitTest.java | package com.baeldung.algorithms.enumstatemachine;
import static org.junit.jupiter.api.Assertions.assertEquals;
import org.junit.jupiter.api.Test;
class LeaveRequestStateUnitTest {
@Test
void givenLeaveRequest_whenStateEscalated_thenResponsibleIsTeamLeader() {
LeaveRequestState state = LeaveRequestState.Escalated;
assertEquals( "Team Leader", state.responsiblePerson());
}
@Test
void givenLeaveRequest_whenStateApproved_thenResponsibleIsDepartmentManager() {
LeaveRequestState state = LeaveRequestState.Approved;
assertEquals( "Department Manager" , state.responsiblePerson());
}
@Test
void givenLeaveRequest_whenNextStateIsCalled_thenStateIsChanged() {
LeaveRequestState state = LeaveRequestState.Submitted;
state = state.nextState();
assertEquals(LeaveRequestState.Escalated, state);
state = state.nextState();
assertEquals(LeaveRequestState.Approved, state);
state = state.nextState();
assertEquals(LeaveRequestState.Approved, state);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/conversion/ByteArrayConverterUnitTest.java | algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/conversion/ByteArrayConverterUnitTest.java | package com.baeldung.algorithms.conversion;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.junit.jupiter.api.Assertions.assertArrayEquals;
import static org.junit.jupiter.api.Assertions.assertThrows;
import org.apache.commons.codec.DecoderException;
import org.hamcrest.text.IsEqualIgnoringCase;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
class ByteArrayConverterUnitTest {
private HexStringConverter hexStringConverter;
@BeforeEach
public void setup() {
hexStringConverter = new HexStringConverter();
}
@Test
void shouldEncodeByteArrayToHexStringUsingBigIntegerToString() {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
if (hexString.charAt(0) == '0') {
hexString = hexString.substring(1);
}
String output = hexStringConverter.encodeUsingBigIntegerToString(bytes);
assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
}
@Test
void shouldEncodeByteArrayToHexStringUsingBigIntegerStringFormat() {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
String output = hexStringConverter.encodeUsingBigIntegerStringFormat(bytes);
assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
}
@Test
void shouldDecodeHexStringToByteArrayUsingBigInteger() {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
byte[] output = hexStringConverter.decodeUsingBigInteger(hexString);
assertArrayEquals(bytes, output);
}
@Test
void shouldEncodeByteArrayToHexStringUsingCharacterConversion() {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
String output = hexStringConverter.encodeHexString(bytes);
assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
}
@Test
void shouldDecodeHexStringToByteArrayUsingCharacterConversion() {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
byte[] output = hexStringConverter.decodeHexString(hexString);
assertArrayEquals(bytes, output);
}
@Test
void shouldDecodeHexToByteWithInvalidHexCharacter() {
assertThrows(IllegalArgumentException.class, () -> {
hexStringConverter.hexToByte("fg");
});
}
@Test
void shouldEncodeByteArrayToHexStringDataTypeConverter() {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
String output = hexStringConverter.encodeUsingDataTypeConverter(bytes);
assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
}
@Test
void shouldDecodeHexStringToByteArrayUsingDataTypeConverter() {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
byte[] output = hexStringConverter.decodeUsingDataTypeConverter(hexString);
assertArrayEquals(bytes, output);
}
@Test
void shouldEncodeByteArrayToHexStringUsingGuava() {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
String output = hexStringConverter.encodeUsingGuava(bytes);
assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
}
@Test
void shouldDecodeHexStringToByteArrayUsingGuava() {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
byte[] output = hexStringConverter.decodeUsingGuava(hexString);
assertArrayEquals(bytes, output);
}
@Test
void shouldEncodeByteArrayToHexStringUsingApacheCommons() throws DecoderException {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
String output = hexStringConverter.encodeUsingApacheCommons(bytes);
assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
}
@Test
void shouldDecodeHexStringToByteArrayUsingApacheCommons() throws DecoderException {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
byte[] output = hexStringConverter.decodeUsingApacheCommons(hexString);
assertArrayEquals(bytes, output);
}
@Test
void shouldEncodeByteArrayToHexStringUsingHexFormat() throws DecoderException {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
String output = hexStringConverter.encodeUsingHexFormat(bytes);
assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
}
@Test
void shouldDecodeHexStringToByteArrayUsingHexFormat() throws DecoderException {
byte[] bytes = getSampleBytes();
String hexString = getSampleHexString();
byte[] output = hexStringConverter.decodeUsingHexFormat(hexString);
assertArrayEquals(bytes, output);
}
private String getSampleHexString() {
return "0af50c0e2d10";
}
private byte[] getSampleBytes() {
return new byte[]{10, -11, 12, 14, 45, 16};
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/maximumsubarray/BruteForceAlgorithmUnitTest.java | algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/maximumsubarray/BruteForceAlgorithmUnitTest.java | package com.baeldung.algorithms.maximumsubarray;
import static org.junit.jupiter.api.Assertions.assertEquals;
import org.junit.jupiter.api.Test;
class BruteForceAlgorithmUnitTest {
@Test
void givenArrayWithNegativeNumberWhenMaximumSubarrayThenReturns6() {
//given
int[] arr = new int[]{-3, 1, -8, 4, -1, 2, 1, -5, 5};
//when
BruteForceAlgorithm algorithm = new BruteForceAlgorithm();
int maximumSum = algorithm.maxSubArray(arr);
//then
assertEquals(6, maximumSum);
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/maximumsubarray/KadaneAlgorithmUnitTest.java | algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/maximumsubarray/KadaneAlgorithmUnitTest.java | package com.baeldung.algorithms.maximumsubarray;
import static org.junit.jupiter.api.Assertions.assertEquals;
import org.junit.jupiter.api.Test;
class KadaneAlgorithmUnitTest {
@Test
void givenArrayWithNegativeNumberWhenMaximumSubarrayThenReturnsExpectedResult() {
//given
int[] arr = new int[] { -3, 1, -8, 4, -1, 2, 1, -5, 5 };
//when
KadaneAlgorithm algorithm = new KadaneAlgorithm();
int maxSum = algorithm.maxSubArraySum(arr);
//then
assertEquals(6, maxSum);
}
@Test
void givenArrayWithAllNegativeNumbersWhenMaximumSubarrayThenReturnsExpectedResult() {
//given
int[] arr = new int[] { -8, -7, -5, -4, -3, -1, -2 };
//when
KadaneAlgorithm algorithm = new KadaneAlgorithm();
int maxSum = algorithm.maxSubArraySum(arr);
//then
assertEquals(-1, maxSum);
}
@Test
void givenArrayWithAllPosiitveNumbersWhenMaximumSubarrayThenReturnsExpectedResult() {
//given
int[] arr = new int[] {4, 1, 3, 2};
//when
KadaneAlgorithm algorithm = new KadaneAlgorithm();
int maxSum = algorithm.maxSubArraySum(arr);
//then
assertEquals(10, maxSum);
}
@Test
void givenArrayToTestStartIndexWhenMaximumSubarrayThenReturnsExpectedResult() {
//given
int[] arr = new int[] { 1, 2, -1, 3, -6, -2 };
//when
KadaneAlgorithm algorithm = new KadaneAlgorithm();
int maxSum = algorithm.maxSubArraySum(arr);
//then
assertEquals(5, maxSum);
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/latlondistance/GeoDistanceUnitTest.java | algorithms-modules/algorithms-miscellaneous-1/src/test/java/com/baeldung/algorithms/latlondistance/GeoDistanceUnitTest.java | package com.baeldung.algorithms.latlondistance;
import static org.junit.jupiter.api.Assertions.assertTrue;
import org.junit.jupiter.api.Test;
class GeoDistanceUnitTest {
@Test
public void testCalculateDistance() {
double lat1 = 40.714268; // New York
double lon1 = -74.005974;
double lat2 = 34.0522; // Los Angeles
double lon2 = -118.2437;
double equirectangularDistance = EquirectangularApproximation.calculateDistance(lat1, lon1, lat2, lon2);
double haversineDistance = HaversineDistance.calculateDistance(lat1, lon1, lat2, lon2);
double vincentyDistance = VincentyDistance.calculateDistance(lat1, lon1, lat2, lon2);
double expectedDistance = 3944;
assertTrue(Math.abs(equirectangularDistance - expectedDistance) < 100);
assertTrue(Math.abs(haversineDistance - expectedDistance) < 10);
assertTrue(Math.abs(vincentyDistance - expectedDistance) < 0.5);
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/permutation/Permutation.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/permutation/Permutation.java | package com.baeldung.algorithms.permutation;
import java.util.Arrays;
import java.util.Collections;
public class Permutation {
public static <T> void printAllRecursive(T[] elements, char delimiter) {
printAllRecursive(elements.length, elements, delimiter);
}
public static <T> void printAllRecursive(int n, T[] elements, char delimiter) {
if(n == 1) {
printArray(elements, delimiter);
} else {
for(int i = 0; i < n-1; i++) {
printAllRecursive(n - 1, elements, delimiter);
if(n % 2 == 0) {
swap(elements, i, n-1);
} else {
swap(elements, 0, n-1);
}
}
printAllRecursive(n - 1, elements, delimiter);
}
}
public static <T> void printAllIterative(int n, T[] elements, char delimiter) {
int[] indexes = new int[n];
for (int i = 0; i < n; i++) {
indexes[i] = 0;
}
printArray(elements, delimiter);
int i = 0;
while (i < n) {
if (indexes[i] < i) {
swap(elements, i % 2 == 0 ? 0: indexes[i], i);
printArray(elements, delimiter);
indexes[i]++;
i = 0;
}
else {
indexes[i] = 0;
i++;
}
}
}
public static <T extends Comparable<T>> void printAllOrdered(T[] elements, char delimiter) {
Arrays.sort(elements);
boolean hasNext = true;
while(hasNext) {
printArray(elements, delimiter);
int k = 0, l = 0;
hasNext = false;
for (int i = elements.length - 1; i > 0; i--) {
if (elements[i].compareTo(elements[i - 1]) > 0) {
k = i - 1;
hasNext = true;
break;
}
}
for (int i = elements.length - 1; i > k; i--) {
if (elements[i].compareTo(elements[k]) > 0) {
l = i;
break;
}
}
swap(elements, k, l);
Collections.reverse(Arrays.asList(elements).subList(k + 1, elements.length));
}
}
public static <T> void printRandom(T[] elements, char delimiter) {
Collections.shuffle(Arrays.asList(elements));
printArray(elements, delimiter);
}
private static <T> void swap(T[] elements, int a, int b) {
T tmp = elements[a];
elements[a] = elements[b];
elements[b] = tmp;
}
private static <T> void printArray(T[] elements, char delimiter) {
String delimiterSpace = delimiter + " ";
for(int i = 0; i < elements.length; i++) {
System.out.print(elements[i] + delimiterSpace);
}
System.out.print('\n');
}
public static void main(String[] argv) {
Integer[] elements = {1,2,3,4};
System.out.println("Rec:");
printAllRecursive(elements, ';');
System.out.println("Iter:");
printAllIterative(elements.length, elements, ';');
System.out.println("Orderes:");
printAllOrdered(elements, ';');
System.out.println("Random:");
printRandom(elements, ';');
System.out.println("Random:");
printRandom(elements, ';');
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/dijkstra/Node.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/dijkstra/Node.java | package com.baeldung.algorithms.dijkstra;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
public class Node {
private String name;
private LinkedList<Node> shortestPath = new LinkedList<>();
private Integer distance = Integer.MAX_VALUE;
private Map<Node, Integer> adjacentNodes = new HashMap<>();
public Node(String name) {
this.name = name;
}
public void addDestination(Node destination, int distance) {
adjacentNodes.put(destination, distance);
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Map<Node, Integer> getAdjacentNodes() {
return adjacentNodes;
}
public void setAdjacentNodes(Map<Node, Integer> adjacentNodes) {
this.adjacentNodes = adjacentNodes;
}
public Integer getDistance() {
return distance;
}
public void setDistance(Integer distance) {
this.distance = distance;
}
public List<Node> getShortestPath() {
return shortestPath;
}
public void setShortestPath(LinkedList<Node> shortestPath) {
this.shortestPath = shortestPath;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/dijkstra/Graph.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/dijkstra/Graph.java | package com.baeldung.algorithms.dijkstra;
import java.util.HashSet;
import java.util.Set;
public class Graph {
private Set<Node> nodes = new HashSet<>();
public void addNode(Node nodeA) {
nodes.add(nodeA);
}
public Set<Node> getNodes() {
return nodes;
}
public void setNodes(Set<Node> nodes) {
this.nodes = nodes;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/dijkstra/Dijkstra.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/dijkstra/Dijkstra.java | package com.baeldung.algorithms.dijkstra;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Map.Entry;
import java.util.Set;
public class Dijkstra {
public static Graph calculateShortestPathFromSource(Graph graph, Node source) {
source.setDistance(0);
Set<Node> settledNodes = new HashSet<>();
Set<Node> unsettledNodes = new HashSet<>();
unsettledNodes.add(source);
while (unsettledNodes.size() != 0) {
Node currentNode = getLowestDistanceNode(unsettledNodes);
unsettledNodes.remove(currentNode);
for (Entry<Node, Integer> adjacencyPair : currentNode.getAdjacentNodes().entrySet()) {
Node adjacentNode = adjacencyPair.getKey();
Integer edgeWeigh = adjacencyPair.getValue();
if (!settledNodes.contains(adjacentNode)) {
CalculateMinimumDistance(adjacentNode, edgeWeigh, currentNode);
unsettledNodes.add(adjacentNode);
}
}
settledNodes.add(currentNode);
}
return graph;
}
private static void CalculateMinimumDistance(Node evaluationNode, Integer edgeWeigh, Node sourceNode) {
Integer sourceDistance = sourceNode.getDistance();
if (sourceDistance + edgeWeigh < evaluationNode.getDistance()) {
evaluationNode.setDistance(sourceDistance + edgeWeigh);
LinkedList<Node> shortestPath = new LinkedList<>(sourceNode.getShortestPath());
shortestPath.add(sourceNode);
evaluationNode.setShortestPath(shortestPath);
}
}
private static Node getLowestDistanceNode(Set<Node> unsettledNodes) {
Node lowestDistanceNode = null;
int lowestDistance = Integer.MAX_VALUE;
for (Node node : unsettledNodes) {
int nodeDistance = node.getDistance();
if (nodeDistance < lowestDistance) {
lowestDistance = nodeDistance;
lowestDistanceNode = node;
}
}
return lowestDistanceNode;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/enumstatemachine/LeaveRequestState.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/enumstatemachine/LeaveRequestState.java | package com.baeldung.algorithms.enumstatemachine;
public enum LeaveRequestState {
Submitted {
@Override
public LeaveRequestState nextState() {
System.out.println("Starting the Leave Request and sending to Team Leader for approval.");
return Escalated;
}
@Override
public String responsiblePerson() {
return "Employee";
}
},
Escalated {
@Override
public LeaveRequestState nextState() {
System.out.println("Reviewing the Leave Request and escalating to Department Manager.");
return Approved;
}
@Override
public String responsiblePerson() {
return "Team Leader";
}
},
Approved {
@Override
public LeaveRequestState nextState() {
System.out.println("Approving the Leave Request.");
return this;
}
@Override
public String responsiblePerson() {
return "Department Manager";
}
};
public abstract String responsiblePerson();
public abstract LeaveRequestState nextState();
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/conversion/HexStringConverter.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/conversion/HexStringConverter.java | package com.baeldung.algorithms.conversion;
import java.math.BigInteger;
import java.util.HexFormat;
import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Hex;
import com.google.common.io.BaseEncoding;
import jakarta.xml.bind.DatatypeConverter;
public class HexStringConverter {
/**
* Create a byte Array from String of hexadecimal digits using Character conversion
* @param hexString - Hexadecimal digits as String
* @return Desired byte Array
*/
public byte[] decodeHexString(String hexString) {
if (hexString.length() % 2 == 1) {
throw new IllegalArgumentException("Invalid hexadecimal String supplied.");
}
byte[] bytes = new byte[hexString.length() / 2];
for (int i = 0; i < hexString.length(); i += 2) {
bytes[i / 2] = hexToByte(hexString.substring(i, i + 2));
}
return bytes;
}
/**
* Create a String of hexadecimal digits from a byte Array using Character conversion
* @param byteArray - The byte Array
* @return Desired String of hexadecimal digits in lower case
*/
public String encodeHexString(byte[] byteArray) {
StringBuffer hexStringBuffer = new StringBuffer();
for (int i = 0; i < byteArray.length; i++) {
hexStringBuffer.append(byteToHex(byteArray[i]));
}
return hexStringBuffer.toString();
}
public String byteToHex(byte num) {
char[] hexDigits = new char[2];
hexDigits[0] = Character.forDigit((num >> 4) & 0xF, 16);
hexDigits[1] = Character.forDigit((num & 0xF), 16);
return new String(hexDigits);
}
public byte hexToByte(String hexString) {
int firstDigit = toDigit(hexString.charAt(0));
int secondDigit = toDigit(hexString.charAt(1));
return (byte) ((firstDigit << 4) + secondDigit);
}
private int toDigit(char hexChar) {
int digit = Character.digit(hexChar, 16);
if(digit == -1) {
throw new IllegalArgumentException("Invalid Hexadecimal Character: "+ hexChar);
}
return digit;
}
public String encodeUsingBigIntegerToString(byte[] bytes) {
BigInteger bigInteger = new BigInteger(1, bytes);
return bigInteger.toString(16);
}
public String encodeUsingBigIntegerStringFormat(byte[] bytes) {
BigInteger bigInteger = new BigInteger(1, bytes);
return String.format("%0" + (bytes.length << 1) + "x", bigInteger);
}
public byte[] decodeUsingBigInteger(String hexString) {
byte[] byteArray = new BigInteger(hexString, 16).toByteArray();
if (byteArray[0] == 0) {
byte[] output = new byte[byteArray.length - 1];
System.arraycopy(byteArray, 1, output, 0, output.length);
return output;
}
return byteArray;
}
public String encodeUsingDataTypeConverter(byte[] bytes) {
return DatatypeConverter.printHexBinary(bytes);
}
public byte[] decodeUsingDataTypeConverter(String hexString) {
return DatatypeConverter.parseHexBinary(hexString);
}
public String encodeUsingApacheCommons(byte[] bytes) {
return Hex.encodeHexString(bytes);
}
public byte[] decodeUsingApacheCommons(String hexString) throws DecoderException {
return Hex.decodeHex(hexString);
}
public String encodeUsingGuava(byte[] bytes) {
return BaseEncoding.base16()
.encode(bytes);
}
public byte[] decodeUsingGuava(String hexString) {
return BaseEncoding.base16()
.decode(hexString.toUpperCase());
}
public String encodeUsingHexFormat(byte[] bytes) {
HexFormat hexFormat = HexFormat.of();
return hexFormat.formatHex(bytes);
}
public byte[] decodeUsingHexFormat(String hexString) {
HexFormat hexFormat = HexFormat.of();
return hexFormat.parseHex(hexString);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/maximumsubarray/BruteForceAlgorithm.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/maximumsubarray/BruteForceAlgorithm.java | package com.baeldung.algorithms.maximumsubarray;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class BruteForceAlgorithm {
private Logger logger = LoggerFactory.getLogger(BruteForceAlgorithm.class.getName());
public int maxSubArray(int[] arr) {
int size = arr.length;
int maximumSubArraySum = Integer.MIN_VALUE;
int start = 0;
int end = 0;
for (int left = 0; left < size; left++) {
int runningWindowSum = 0;
for (int right = left; right < size; right++) {
runningWindowSum += arr[right];
if (runningWindowSum > maximumSubArraySum) {
maximumSubArraySum = runningWindowSum;
start = left;
end = right;
}
}
}
logger.info("Found Maximum Subarray between {} and {}", start, end);
return maximumSubArraySum;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/maximumsubarray/KadaneAlgorithm.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/maximumsubarray/KadaneAlgorithm.java | package com.baeldung.algorithms.maximumsubarray;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class KadaneAlgorithm {
private Logger logger = LoggerFactory.getLogger(KadaneAlgorithm.class.getName());
public int maxSubArraySum(int[] arr) {
int size = arr.length;
int start = 0;
int end = 0;
int maxSoFar = arr[0], maxEndingHere = arr[0];
for (int i = 1; i < size; i++) {
maxEndingHere = maxEndingHere + arr[i];
if (arr[i] > maxEndingHere) {
maxEndingHere = arr[i];
if (maxSoFar < maxEndingHere) {
start = i;
}
}
if (maxSoFar < maxEndingHere) {
maxSoFar = maxEndingHere;
end = i;
}
}
logger.info("Found Maximum Subarray between {} and {}", Math.min(start, end), end);
return maxSoFar;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/latlondistance/HaversineDistance.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/latlondistance/HaversineDistance.java | package com.baeldung.algorithms.latlondistance;
public class HaversineDistance {
private static final int EARTH_RADIUS = 6371; // Approx Earth radius in KM
public static double calculateDistance(double startLat, double startLong,
double endLat, double endLong) {
double dLat = Math.toRadians((endLat - startLat));
double dLong = Math.toRadians((endLong - startLong));
startLat = Math.toRadians(startLat);
endLat = Math.toRadians(endLat);
double a = haversine(dLat) + Math.cos(startLat) * Math.cos(endLat) * haversine(dLong);
double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
return EARTH_RADIUS * c;
}
public static double haversine(double val) {
return Math.pow(Math.sin(val / 2), 2);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/latlondistance/EquirectangularApproximation.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/latlondistance/EquirectangularApproximation.java | package com.baeldung.algorithms.latlondistance;
public class EquirectangularApproximation {
private static final int EARTH_RADIUS = 6371; // Approx Earth radius in KM
public static double calculateDistance(double lat1, double lon1, double lat2, double lon2) {
double lat1Rad = Math.toRadians(lat1);
double lat2Rad = Math.toRadians(lat2);
double lon1Rad = Math.toRadians(lon1);
double lon2Rad = Math.toRadians(lon2);
double x = (lon2Rad - lon1Rad) * Math.cos((lat1Rad + lat2Rad) / 2);
double y = (lat2Rad - lat1Rad);
double distance = Math.sqrt(x * x + y * y) * EARTH_RADIUS;
return distance;
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/latlondistance/VincentyDistance.java | algorithms-modules/algorithms-miscellaneous-1/src/main/java/com/baeldung/algorithms/latlondistance/VincentyDistance.java | package com.baeldung.algorithms.latlondistance;
public class VincentyDistance {
// Constants for WGS84 ellipsoid model of Earth
private static final double SEMI_MAJOR_AXIS_MT = 6378137;
private static final double SEMI_MINOR_AXIS_MT = 6356752.314245;
private static final double FLATTENING = 1 / 298.257223563;
private static final double ERROR_TOLERANCE = 1e-12;
public static double calculateDistance(double latitude1, double longitude1, double latitude2, double longitude2) {
double U1 = Math.atan((1 - FLATTENING) * Math.tan(Math.toRadians(latitude1)));
double U2 = Math.atan((1 - FLATTENING) * Math.tan(Math.toRadians(latitude2)));
double sinU1 = Math.sin(U1);
double cosU1 = Math.cos(U1);
double sinU2 = Math.sin(U2);
double cosU2 = Math.cos(U2);
double longitudeDifference = Math.toRadians(longitude2 - longitude1);
double previousLongitudeDifference;
double sinSigma, cosSigma, sigma, sinAlpha, cosSqAlpha, cos2SigmaM;
do {
sinSigma = Math.sqrt(Math.pow(cosU2 * Math.sin(longitudeDifference), 2) +
Math.pow(cosU1 * sinU2 - sinU1 * cosU2 * Math.cos(longitudeDifference), 2));
cosSigma = sinU1 * sinU2 + cosU1 * cosU2 * Math.cos(longitudeDifference);
sigma = Math.atan2(sinSigma, cosSigma);
sinAlpha = cosU1 * cosU2 * Math.sin(longitudeDifference) / sinSigma;
cosSqAlpha = 1 - Math.pow(sinAlpha, 2);
cos2SigmaM = cosSigma - 2 * sinU1 * sinU2 / cosSqAlpha;
if (Double.isNaN(cos2SigmaM)) {
cos2SigmaM = 0;
}
previousLongitudeDifference = longitudeDifference;
double C = FLATTENING / 16 * cosSqAlpha * (4 + FLATTENING * (4 - 3 * cosSqAlpha));
longitudeDifference = Math.toRadians(longitude2 - longitude1) + (1 - C) * FLATTENING * sinAlpha *
(sigma + C * sinSigma * (cos2SigmaM + C * cosSigma * (-1 + 2 * Math.pow(cos2SigmaM, 2))));
} while (Math.abs(longitudeDifference - previousLongitudeDifference) > ERROR_TOLERANCE);
double uSq = cosSqAlpha * (Math.pow(SEMI_MAJOR_AXIS_MT, 2) - Math.pow(SEMI_MINOR_AXIS_MT, 2)) / Math.pow(SEMI_MINOR_AXIS_MT, 2);
double A = 1 + uSq / 16384 * (4096 + uSq * (-768 + uSq * (320 - 175 * uSq)));
double B = uSq / 1024 * (256 + uSq * (-128 + uSq * (74 - 47 * uSq)));
double deltaSigma = B * sinSigma * (cos2SigmaM + B / 4 * (cosSigma * (-1 + 2 * Math.pow(cos2SigmaM, 2)) -
B / 6 * cos2SigmaM * (-3 + 4 * Math.pow(sinSigma, 2)) * (-3 + 4 * Math.pow(cos2SigmaM, 2))));
double distanceMt = SEMI_MINOR_AXIS_MT * A * (sigma - deltaSigma);
return distanceMt / 1000;
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/binarysearch/BinarySearchUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/binarysearch/BinarySearchUnitTest.java | package com.baeldung.algorithms.binarysearch;
import static org.junit.jupiter.api.Assertions.assertEquals;
import java.util.Arrays;
import java.util.List;
import org.junit.jupiter.api.Test;
class BinarySearchUnitTest {
int[] sortedArray = { 0, 1, 2, 3, 4, 5, 5, 6, 7, 8, 9, 9 };
int key = 6;
int expectedIndexForSearchKey = 7;
int low = 0;
int high = sortedArray.length - 1;
List<Integer> sortedList = Arrays.asList(0, 1, 2, 3, 4, 5, 5, 6, 7, 8, 9, 9);
@Test
void givenASortedArrayOfIntegers_whenBinarySearchRunIterativelyForANumber_thenGetIndexOfTheNumber() {
BinarySearch binSearch = new BinarySearch();
assertEquals(expectedIndexForSearchKey, binSearch.runBinarySearchIteratively(sortedArray, key, low, high));
}
@Test
void givenASortedArrayOfIntegers_whenBinarySearchRunRecursivelyForANumber_thenGetIndexOfTheNumber() {
BinarySearch binSearch = new BinarySearch();
assertEquals(expectedIndexForSearchKey, binSearch.runBinarySearchRecursively(sortedArray, key, low, high));
}
@Test
void givenASortedArrayOfIntegers_whenBinarySearchRunUsingArraysClassStaticMethodForANumber_thenGetIndexOfTheNumber() {
BinarySearch binSearch = new BinarySearch();
assertEquals(expectedIndexForSearchKey, binSearch.runBinarySearchUsingJavaArrays(sortedArray, key));
}
@Test
void givenASortedListOfIntegers_whenBinarySearchRunUsingCollectionsClassStaticMethodForANumber_thenGetIndexOfTheNumber() {
BinarySearch binSearch = new BinarySearch();
assertEquals(expectedIndexForSearchKey, binSearch.runBinarySearchUsingJavaCollections(sortedList, key));
}
@Test
void givenSortedListOfIntegers_whenBinarySearchOnSortedArraysWithDuplicates_thenGetIndexOfDuplicates() {
int[] sortedArray = { 1, 2, 3, 4, 5, 5, 5, 5, 5, 6, 7, 7, 8, 9 };
BinarySearch binSearch = new BinarySearch();
assertEquals(Arrays.asList(4, 5, 6, 7, 8), binSearch.runBinarySearchOnSortedArraysWithDuplicates(sortedArray, 5));
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/suffixtree/SuffixTreeUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/suffixtree/SuffixTreeUnitTest.java | package com.baeldung.algorithms.suffixtree;
import static org.junit.jupiter.api.Assertions.assertArrayEquals;
import java.util.List;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
class SuffixTreeUnitTest {
private static final Logger LOGGER = LoggerFactory.getLogger(SuffixTreeUnitTest.class);
private static SuffixTree suffixTree;
@BeforeAll
public static void setUp() {
suffixTree = new SuffixTree("havanabanana");
printTree();
}
@Test
void givenSuffixTree_whenSearchingForA_thenReturn6Matches() {
List<String> matches = suffixTree.searchText("a");
matches.stream()
.forEach(m -> LOGGER.debug(m));
assertArrayEquals(new String[] { "h[a]vanabanana", "hav[a]nabanana", "havan[a]banana", "havanab[a]nana", "havanaban[a]na", "havanabanan[a]" }, matches.toArray());
}
@Test
void givenSuffixTree_whenSearchingForNab_thenReturn1Match() {
List<String> matches = suffixTree.searchText("nab");
matches.stream()
.forEach(m -> LOGGER.debug(m));
assertArrayEquals(new String[] { "hava[nab]anana" }, matches.toArray());
}
@Test
void givenSuffixTree_whenSearchingForNag_thenReturnNoMatches() {
List<String> matches = suffixTree.searchText("nag");
matches.stream()
.forEach(m -> LOGGER.debug(m));
assertArrayEquals(new String[] {}, matches.toArray());
}
@Test
void givenSuffixTree_whenSearchingForBanana_thenReturn2Matches() {
List<String> matches = suffixTree.searchText("ana");
matches.stream()
.forEach(m -> LOGGER.debug(m));
assertArrayEquals(new String[] { "hav[ana]banana", "havanab[ana]na", "havanaban[ana]" }, matches.toArray());
}
@Test
void givenSuffixTree_whenSearchingForNa_thenReturn4Matches() {
List<String> matches = suffixTree.searchText("na");
matches.stream()
.forEach(m -> LOGGER.debug(m));
assertArrayEquals(new String[] { "hava[na]banana", "havanaba[na]na", "havanabana[na]" }, matches.toArray());
}
@Test
void givenSuffixTree_whenSearchingForX_thenReturnNoMatches() {
List<String> matches = suffixTree.searchText("x");
matches.stream()
.forEach(m -> LOGGER.debug(m));
assertArrayEquals(new String[] {}, matches.toArray());
}
private static void printTree() {
suffixTree.printTree();
LOGGER.debug("\n" + suffixTree.printTree());
LOGGER.debug("==============================================");
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/breadthfirstsearch/BreadthFirstSearchAlgorithmUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/breadthfirstsearch/BreadthFirstSearchAlgorithmUnitTest.java | package com.baeldung.algorithms.breadthfirstsearch;
import org.junit.jupiter.api.Test;
import static org.assertj.core.api.Assertions.assertThat;
class BreadthFirstSearchAlgorithmUnitTest {
private Tree<Integer> root;
private Tree<Integer> rootFirstChild;
private Tree<Integer> depthMostChild;
private Tree<Integer> rootSecondChild;
private Node<Integer> start;
private Node<Integer> firstNeighbor;
private Node<Integer> firstNeighborNeighbor;
private Node<Integer> secondNeighbor;
@Test
void givenTree_whenSearchTen_thenRoot() {
initTree();
assertThat(BreadthFirstSearchAlgorithm.search(10, root)).isPresent().contains(root);
}
@Test
void givenTree_whenSearchThree_thenDepthMostValue() {
initTree();
assertThat(BreadthFirstSearchAlgorithm.search(3, root)).isPresent().contains(depthMostChild);
}
@Test
void givenTree_whenSearchFour_thenRootSecondChild() {
initTree();
assertThat(BreadthFirstSearchAlgorithm.search(4, root)).isPresent().contains(rootSecondChild);
}
@Test
void givenTree_whenSearchFive_thenNotFound() {
initTree();
assertThat(BreadthFirstSearchAlgorithm.search(5, root)).isEmpty();
}
private void initTree() {
root = Tree.of(10);
rootFirstChild = root.addChild(2);
depthMostChild = rootFirstChild.addChild(3);
rootSecondChild = root.addChild(4);
}
@Test
void givenNode_whenSearchTen_thenStart() {
initNode();
assertThat(BreadthFirstSearchAlgorithm.search(10, firstNeighborNeighbor)).isPresent().contains(start);
}
@Test
void givenNode_whenSearchThree_thenNeighborNeighbor() {
initNode();
assertThat(BreadthFirstSearchAlgorithm.search(3, firstNeighborNeighbor)).isPresent().contains(firstNeighborNeighbor);
}
@Test
void givenNode_whenSearchFour_thenSecondNeighbor() {
initNode();
assertThat(BreadthFirstSearchAlgorithm.search(4, firstNeighborNeighbor)).isPresent().contains(secondNeighbor);
}
@Test
void givenNode_whenSearchFive_thenNotFound() {
initNode();
assertThat(BreadthFirstSearchAlgorithm.search(5, firstNeighborNeighbor)).isEmpty();
}
private void initNode() {
start = new Node<>(10);
firstNeighbor = new Node<>(2);
start.connect(firstNeighbor);
firstNeighborNeighbor = new Node<>(3);
firstNeighbor.connect(firstNeighborNeighbor);
firstNeighborNeighbor.connect(start);
secondNeighbor = new Node<>(4);
start.connect(secondNeighbor);
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/mcts/MCTSUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/mcts/MCTSUnitTest.java | package com.baeldung.algorithms.mcts;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertTrue;
import java.util.List;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import com.baeldung.algorithms.mcts.montecarlo.MonteCarloTreeSearch;
import com.baeldung.algorithms.mcts.montecarlo.State;
import com.baeldung.algorithms.mcts.montecarlo.UCT;
import com.baeldung.algorithms.mcts.tictactoe.Board;
import com.baeldung.algorithms.mcts.tictactoe.Position;
import com.baeldung.algorithms.mcts.tree.Tree;
class MCTSUnitTest {
private Tree gameTree;
private MonteCarloTreeSearch mcts;
@BeforeEach
public void initGameTree() {
gameTree = new Tree();
mcts = new MonteCarloTreeSearch();
}
@Test
void givenStats_whenGetUCTForNode_thenUCTMatchesWithManualData() {
double uctValue = 15.79;
assertEquals(UCT.uctValue(600, 300, 20), uctValue, 0.01);
}
@Test
void giveninitBoardState_whenGetAllPossibleStates_thenNonEmptyList() {
State initState = gameTree.getRoot().getState();
List<State> possibleStates = initState.getAllPossibleStates();
assertTrue(possibleStates.size() > 0);
}
@Test
void givenEmptyBoard_whenPerformMove_thenLessAvailablePossitions() {
Board board = new Board();
int initAvailablePositions = board.getEmptyPositions().size();
board.performMove(Board.P1, new Position(1, 1));
int availablePositions = board.getEmptyPositions().size();
assertTrue(initAvailablePositions > availablePositions);
}
@Test
void givenEmptyBoard_whenSimulateInterAIPlay_thenGameDraw() {
Board board = new Board();
int player = Board.P1;
int totalMoves = Board.DEFAULT_BOARD_SIZE * Board.DEFAULT_BOARD_SIZE;
for (int i = 0; i < totalMoves; i++) {
board = mcts.findNextMove(board, player);
if (board.checkStatus() != -1) {
break;
}
player = 3 - player;
}
int winStatus = board.checkStatus();
assertEquals(Board.DRAW, winStatus);
}
@Test
void givenEmptyBoard_whenLevel1VsLevel3_thenLevel3WinsOrDraw() {
Board board = new Board();
MonteCarloTreeSearch mcts1 = new MonteCarloTreeSearch();
mcts1.setLevel(1);
MonteCarloTreeSearch mcts3 = new MonteCarloTreeSearch();
mcts3.setLevel(3);
int player = Board.P1;
int totalMoves = Board.DEFAULT_BOARD_SIZE * Board.DEFAULT_BOARD_SIZE;
for (int i = 0; i < totalMoves; i++) {
if (player == Board.P1)
board = mcts3.findNextMove(board, player);
else
board = mcts1.findNextMove(board, player);
if (board.checkStatus() != -1) {
break;
}
player = 3 - player;
}
int winStatus = board.checkStatus();
assertTrue(winStatus == Board.DRAW || winStatus == Board.P1);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/dfs/GraphUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/dfs/GraphUnitTest.java | package com.baeldung.algorithms.dfs;
import java.util.Arrays;
import java.util.List;
import org.junit.Assert;
import org.junit.jupiter.api.Test;
class GraphUnitTest {
@Test
void givenDirectedGraph_whenDFS_thenPrintAllValues() {
Graph graph = createDirectedGraph();
boolean[] visited;
visited = graph.dfs(0);
boolean[] expected = new boolean[]{true, true, true, true, true, true};
Assert.assertArrayEquals(expected, visited);
visited = graph.dfsWithoutRecursion(0);
Assert.assertArrayEquals(expected, visited);
}
@Test
void givenDirectedGraph_whenGetTopologicalSort_thenPrintValuesSorted() {
Graph graph = createDirectedGraph();
List<Integer> list = graph.topologicalSort(0);
System.out.println(list);
List<Integer> expected = Arrays.asList(0, 2, 1, 3, 4, 5);
Assert.assertEquals(expected, list);
}
private Graph createDirectedGraph() {
Graph graph = new Graph();
graph.addVertex(0);
graph.addVertex(1);
graph.addVertex(2);
graph.addVertex(3);
graph.addVertex(4);
graph.addVertex(5);
graph.addEdge(0, 1);
graph.addEdge(0, 2);
graph.addEdge(1, 3);
graph.addEdge(2, 3);
graph.addEdge(3, 4);
graph.addEdge(4, 5);
return graph;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/dfs/BinaryTreeUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/dfs/BinaryTreeUnitTest.java | package com.baeldung.algorithms.dfs;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertTrue;
import org.junit.jupiter.api.Test;
class BinaryTreeUnitTest {
@Test
void givenABinaryTree_WhenAddingElements_ThenTreeNotEmpty() {
BinaryTree bt = createBinaryTree();
assertFalse(bt.isEmpty());
}
@Test
void givenABinaryTree_WhenAddingElements_ThenTreeContainsThoseElements() {
BinaryTree bt = createBinaryTree();
assertTrue(bt.containsNode(6));
assertTrue(bt.containsNode(4));
assertFalse(bt.containsNode(1));
}
@Test
void givenABinaryTree_WhenAddingExistingElement_ThenElementIsNotAdded() {
BinaryTree bt = createBinaryTree();
int initialSize = bt.getSize();
assertTrue(bt.containsNode(3));
bt.add(3);
assertEquals(initialSize, bt.getSize());
}
@Test
void givenABinaryTree_WhenLookingForNonExistingElement_ThenReturnsFalse() {
BinaryTree bt = createBinaryTree();
assertFalse(bt.containsNode(99));
}
@Test
void givenABinaryTree_WhenDeletingElements_ThenTreeDoesNotContainThoseElements() {
BinaryTree bt = createBinaryTree();
assertTrue(bt.containsNode(9));
bt.delete(9);
assertFalse(bt.containsNode(9));
}
@Test
void givenABinaryTree_WhenDeletingNonExistingElement_ThenTreeDoesNotDelete() {
BinaryTree bt = createBinaryTree();
int initialSize = bt.getSize();
assertFalse(bt.containsNode(99));
bt.delete(99);
assertFalse(bt.containsNode(99));
assertEquals(initialSize, bt.getSize());
}
@Test
void it_deletes_the_root() {
int value = 12;
BinaryTree bt = new BinaryTree();
bt.add(value);
assertTrue(bt.containsNode(value));
bt.delete(value);
assertFalse(bt.containsNode(value));
}
@Test
void givenABinaryTree_WhenTraversingInOrder_ThenPrintValues() {
BinaryTree bt = createBinaryTree();
bt.traverseInOrder(bt.root);
System.out.println();
bt.traverseInOrderWithoutRecursion();
}
@Test
void givenABinaryTree_WhenTraversingPreOrder_ThenPrintValues() {
BinaryTree bt = createBinaryTree();
bt.traversePreOrder(bt.root);
System.out.println();
bt.traversePreOrderWithoutRecursion();
}
@Test
void givenABinaryTree_WhenTraversingPostOrder_ThenPrintValues() {
BinaryTree bt = createBinaryTree();
bt.traversePostOrder(bt.root);
System.out.println();
bt.traversePostOrderWithoutRecursion();
}
private BinaryTree createBinaryTree() {
BinaryTree bt = new BinaryTree();
bt.add(6);
bt.add(4);
bt.add(8);
bt.add(3);
bt.add(5);
bt.add(7);
bt.add(9);
return bt;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/kthsmallest/KthSmallestUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/kthsmallest/KthSmallestUnitTest.java | package com.baeldung.algorithms.kthsmallest;
import org.junit.jupiter.api.Nested;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.function.Executable;
import java.util.*;
import static com.baeldung.algorithms.kthsmallest.KthSmallest.*;
import static org.junit.jupiter.api.Assertions.*;
class KthSmallestUnitTest {
@Nested
class Exceptions {
@Test
void when_at_least_one_list_is_null_then_an_exception_is_thrown() {
Executable executable1 = () -> findKthSmallestElement(1, null, null);
Executable executable2 = () -> findKthSmallestElement(1, new int[]{2}, null);
Executable executable3 = () -> findKthSmallestElement(1, null, new int[]{2});
assertThrows(IllegalArgumentException.class, executable1);
assertThrows(IllegalArgumentException.class, executable2);
assertThrows(IllegalArgumentException.class, executable3);
}
@Test
void when_at_least_one_list_is_empty_then_an_exception_is_thrown() {
Executable executable1 = () -> findKthSmallestElement(1, new int[]{}, new int[]{2});
Executable executable2 = () -> findKthSmallestElement(1, new int[]{2}, new int[]{});
Executable executable3 = () -> findKthSmallestElement(1, new int[]{}, new int[]{});
assertThrows(IllegalArgumentException.class, executable1);
assertThrows(IllegalArgumentException.class, executable2);
assertThrows(IllegalArgumentException.class, executable3);
}
@Test
void when_k_is_smaller_than_0_then_an_exception_is_thrown() {
Executable executable1 = () -> findKthSmallestElement(-1, new int[]{2}, new int[]{2});
assertThrows(IllegalArgumentException.class, executable1);
}
@Test
void when_k_is_smaller_than_1_then_an_exception_is_thrown() {
Executable executable1 = () -> findKthSmallestElement(0, new int[]{2}, new int[]{2});
assertThrows(IllegalArgumentException.class, executable1);
}
@Test
void when_k_bigger_then_the_two_lists_then_an_exception_is_thrown() {
Executable executable1 = () -> findKthSmallestElement(6, new int[]{1, 5, 6}, new int[]{2, 5});
assertThrows(NoSuchElementException.class, executable1);
}
}
@Nested
class K_is_smaller_than_the_size_of_list1_and_the_size_of_list2 {
@Test
public void when_k_is_1_then_the_smallest_element_is_returned_from_list1() {
int result = findKthSmallestElement(1, new int[]{2, 7}, new int[]{3, 5});
assertEquals(2, result);
}
@Test
public void when_k_is_1_then_the_smallest_element_is_returned_list2() {
int result = findKthSmallestElement(1, new int[]{3, 5}, new int[]{2, 7});
assertEquals(2, result);
}
@Test
public void when_kth_element_is_smallest_element_and_occurs_in_both_lists() {
int[] list1 = new int[]{1, 2, 3};
int[] list2 = new int[]{1, 2, 3};
int result = findKthSmallestElement(1, list1, list2);
assertEquals(1, result);
}
@Test
public void when_kth_element_is_smallest_element_and_occurs_in_both_lists2() {
int[] list1 = new int[]{1, 2, 3};
int[] list2 = new int[]{1, 2, 3};
int result = findKthSmallestElement(2, list1, list2);
assertEquals(1, result);
}
@Test
public void when_kth_element_is_largest_element_and_occurs_in_both_lists_1() {
int[] list1 = new int[]{1, 2, 3};
int[] list2 = new int[]{1, 2, 3};
int result = findKthSmallestElement(5, list1, list2);
assertEquals(3, result);
}
@Test
public void when_kth_element_is_largest_element_and_occurs_in_both_lists_2() {
int[] list1 = new int[]{1, 2, 3};
int[] list2 = new int[]{1, 2, 3};
int result = findKthSmallestElement(6, list1, list2);
assertEquals(3, result);
}
@Test
public void when_kth_element_and_occurs_in_both_lists() {
int[] list1 = new int[]{1, 2, 3};
int[] list2 = new int[]{0, 2, 3};
int result = findKthSmallestElement(3, list1, list2);
assertEquals(2, result);
}
@Test
public void and_kth_element_is_in_first_list() {
int[] list1 = new int[]{1,2,3,4};
int[] list2 = new int[]{1,3,4,5};
int result = findKthSmallestElement(3, list1, list2);
assertEquals(2, result);
}
@Test
public void and_kth_is_in_second_list() {
int[] list1 = new int[]{1,3,4,4};
int[] list2 = new int[]{1,2,4,5};
int result = findKthSmallestElement(3, list1, list2);
assertEquals(2, result);
}
@Test
public void and_elements_in_first_list_are_all_smaller_than_second_list() {
int[] list1 = new int[]{1,3,7,9};
int[] list2 = new int[]{11,12,14,15};
int result = findKthSmallestElement(3, list1, list2);
assertEquals(7, result);
}
@Test
public void and_elements_in_first_list_are_all_smaller_than_second_list2() {
int[] list1 = new int[]{1,3,7,9};
int[] list2 = new int[]{11,12,14,15};
int result = findKthSmallestElement(4, list1, list2);
assertEquals(9, result);
}
@Test
public void and_only_elements_from_second_list_are_part_of_result() {
int[] list1 = new int[]{11,12,14,15};
int[] list2 = new int[]{1,3,7,9};
int result = findKthSmallestElement(3, list1, list2);
assertEquals(7, result);
}
@Test
public void and_only_elements_from_second_list_are_part_of_result2() {
int[] list1 = new int[]{11,12,14,15};
int[] list2 = new int[]{1,3,7,9};
int result = findKthSmallestElement(4, list1, list2);
assertEquals(9, result);
}
}
@Nested
class K_is_bigger_than_the_size_of_at_least_one_of_the_lists {
@Test
public void k_is_smaller_than_list1_and_bigger_than_list2() {
int[] list1 = new int[]{1, 2, 3, 4, 7, 9};
int[] list2 = new int[]{1, 2, 3};
int result = findKthSmallestElement(5, list1, list2);
assertEquals(3, result);
}
@Test
public void k_is_bigger_than_list1_and_smaller_than_list2() {
int[] list1 = new int[]{1, 2, 3};
int[] list2 = new int[]{1, 2, 3, 4, 7, 9};
int result = findKthSmallestElement(5, list1, list2);
assertEquals(3, result);
}
@Test
public void when_k_is_bigger_than_the_size_of_both_lists_and_elements_in_second_list_are_all_smaller_than_first_list() {
int[] list1 = new int[]{9, 11, 13, 55};
int[] list2 = new int[]{1, 2, 3, 7};
int result = findKthSmallestElement(6, list1, list2);
assertEquals(11, result);
}
@Test
public void when_k_is_bigger_than_the_size_of_both_lists_and_elements_in_second_list_are_all_bigger_than_first_list() {
int[] list1 = new int[]{1, 2, 3, 7};
int[] list2 = new int[]{9, 11, 13, 55};
int result = findKthSmallestElement(6, list1, list2);
assertEquals(11, result);
}
@Test
public void when_k_is_bigger_than_the_size_of_both_lists() {
int[] list1 = new int[]{3, 7, 9, 11, 55};
int[] list2 = new int[]{1, 2, 3, 7, 13};
int result = findKthSmallestElement(7, list1, list2);
assertEquals(9, result);
}
@Test
public void when_k_is_bigger_than_the_size_of_both_lists_and_list1_has_more_elements_than_list2() {
int[] list1 = new int[]{3, 7, 9, 11, 55, 77, 100, 200};
int[] list2 = new int[]{1, 2, 3, 7, 13};
int result = findKthSmallestElement(11, list1, list2);
assertEquals(77, result);
}
@Test
public void max_test() {
int[] list1 = new int[]{100, 200};
int[] list2 = new int[]{1, 2, 3};
int result = findKthSmallestElement(4, list1, list2);
assertEquals(100, result);
}
@Test
public void max_test2() {
int[] list1 = new int[]{100, 200};
int[] list2 = new int[]{1, 2, 3};
int result = findKthSmallestElement(5, list1, list2);
assertEquals(200, result);
}
@Test
public void when_k_is_smaller_than_the_size_of_both_lists_and_kth_element_in_list2() {
int[] list1 = new int[]{1, 2, 5};
int[] list2 = new int[]{1, 3, 4, 7};
int result = findKthSmallestElement(4, list1, list2);
assertEquals(3, result);
}
@Test
public void when_k_is_smaller_than_the_size_of_both_lists_and_kth_element_is_smallest_in_list2() {
int[] list1 = new int[]{1, 2, 5};
int[] list2 = new int[]{3, 4, 7};
int result = findKthSmallestElement(3, list1, list2);
assertEquals(3, result);
}
@Test
public void when_k_is_smaller_than_the_size_of_both_lists_and_kth_element_is_smallest_in_list23() {
int[] list1 = new int[]{3, 11, 27, 53, 90};
int[] list2 = new int[]{4, 20, 21, 100};
int result = findKthSmallestElement(5, list1, list2);
assertEquals(21, result);
}
}
// @Test
// public void randomTests() {
// IntStream.range(1, 100000).forEach(i -> random());
// }
private void random() {
Random random = new Random();
int length1 = (Math.abs(random.nextInt())) % 1000 + 1;
int length2 = (Math.abs(random.nextInt())) % 1000 + 1;
int[] list1 = sortedRandomIntArrayOfLength(length1);
int[] list2 = sortedRandomIntArrayOfLength(length2);
int k = (Math.abs(random.nextInt()) % (length1 + length2)) + 1 ;
int result = findKthSmallestElement(k, list1, list2);
int result2 = getKthElementSorted(list1, list2, k);
int result3 = getKthElementMerge(list1, list2, k);
assertEquals(result2, result);
assertEquals(result2, result3);
}
private int[] sortedRandomIntArrayOfLength(int length) {
int[] intArray = new Random().ints(length).toArray();
Arrays.sort(intArray);
return intArray;
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/firstnonrepeating/FirstNonRepeatingElementUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/firstnonrepeating/FirstNonRepeatingElementUnitTest.java | package com.baeldung.algorithms.firstnonrepeating;
import static org.junit.jupiter.api.Assertions.assertEquals;
import java.util.Arrays;
import java.util.List;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
public class FirstNonRepeatingElementUnitTest {
private List<Integer> list;
@BeforeEach
void setUp() {
list = Arrays.asList(1, 2, 3, 2, 1, 4, 5, 4);
}
@Test
void whenUsingForLoop_thenReturnFirstNonRepeatingElement() {
int result = FirstNonRepeatingElement.findFirstNonRepeatingUsingForLoop(list);
assertEquals(3, result);
}
@Test
void whenUsingIndexOf_thenReturnFirstNonRepeatingElement() {
int result = FirstNonRepeatingElement.findFirstNonRepeatedElementUsingIndex(list);
assertEquals(3, result);
}
@Test
void whenUsingHashMap_thenReturnFirstNonRepeatingElement() {
int result = FirstNonRepeatingElement.findFirstNonRepeatingUsingHashMap(list);
assertEquals(3, result);
}
@Test
void whenUsingArray_thenReturnFirstNonRepeatingElement() {
int result = FirstNonRepeatingElement.findFirstNonRepeatingUsingArray(list);
assertEquals(3, result);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/quadtree/QuadTreeSearchUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/quadtree/QuadTreeSearchUnitTest.java | package com.baeldung.algorithms.quadtree;
import static org.junit.jupiter.api.Assertions.assertArrayEquals;
import static org.junit.jupiter.api.Assertions.assertEquals;
import java.util.List;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
class QuadTreeSearchUnitTest {
private static final Logger LOGGER = LoggerFactory.getLogger(QuadTreeSearchUnitTest.class);
private static QuadTree quadTree;
@BeforeAll
public static void setUp() {
Region area = new Region(0, 0, 400, 400);
quadTree = new QuadTree(area);
float[][] points = new float[][] { { 21, 25 }, { 55, 53 }, { 70, 318 }, { 98, 302 },
{ 49, 229 }, { 135, 229 }, { 224, 292 }, { 206, 321 }, { 197, 258 }, { 245, 238 } };
for (int i = 0; i < points.length; i++) {
Point point = new Point(points[i][0], points[i][1]);
quadTree.addPoint(point);
}
LOGGER.debug("\n" + quadTree.printTree(""));
LOGGER.debug("==============================================");
}
@Test
void givenQuadTree_whenSearchingForRange_thenReturn1MatchingItem() {
Region searchArea = new Region(200, 200, 250, 250);
List<Point> result = quadTree.search(searchArea, null, "");
LOGGER.debug(result.toString());
LOGGER.debug(quadTree.printSearchTraversePath());
assertEquals(1, result.size());
assertArrayEquals(new float[] { 245, 238 },
new float[]{result.get(0).getX(), result.get(0).getY() }, 0);
}
@Test
void givenQuadTree_whenSearchingForRange_thenReturn2MatchingItems() {
Region searchArea = new Region(0, 0, 100, 100);
List<Point> result = quadTree.search(searchArea, null, "");
LOGGER.debug(result.toString());
LOGGER.debug(quadTree.printSearchTraversePath());
assertEquals(2, result.size());
assertArrayEquals(new float[] { 21, 25 },
new float[]{result.get(0).getX(), result.get(0).getY() }, 0);
assertArrayEquals(new float[] { 55, 53 },
new float[]{result.get(1).getX(), result.get(1).getY() }, 0);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/textsearch/TextSearchAlgorithmsUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/textsearch/TextSearchAlgorithmsUnitTest.java | package com.baeldung.algorithms.textsearch;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertTrue;
import org.junit.jupiter.api.Test;
class TextSearchAlgorithmsUnitTest {
@Test
void testStringSearchAlgorithms() {
String text = "This is some nice text.";
String pattern = "some";
int realPosition = text.indexOf(pattern);
assertEquals(TextSearchAlgorithms.simpleTextSearch(pattern.toCharArray(), text.toCharArray()), realPosition);
assertEquals(TextSearchAlgorithms.RabinKarpMethod(pattern.toCharArray(), text.toCharArray()), realPosition);
assertEquals(TextSearchAlgorithms.KnuthMorrisPrattSearch(pattern.toCharArray(), text.toCharArray()) , realPosition);
assertEquals(TextSearchAlgorithms.BoyerMooreHorspoolSimpleSearch(pattern.toCharArray(), text.toCharArray()), realPosition);
assertEquals(TextSearchAlgorithms.BoyerMooreHorspoolSearch(pattern.toCharArray(), text.toCharArray()), realPosition);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/interpolationsearch/InterpolationSearchUnitTest.java | algorithms-modules/algorithms-searching/src/test/java/com/baeldung/algorithms/interpolationsearch/InterpolationSearchUnitTest.java | package com.baeldung.algorithms.interpolationsearch;
import static org.junit.jupiter.api.Assertions.assertEquals;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
class InterpolationSearchUnitTest {
private int[] myData;
@BeforeEach
public void setUp() {
myData = new int[]{13,21,34,55,69,73,84,101};
}
@Test
void givenSortedArray_whenLookingFor84_thenReturn6() {
int pos = InterpolationSearch.interpolationSearch(myData, 84);
assertEquals(6, pos);
}
@Test
void givenSortedArray_whenLookingFor19_thenReturnMinusOne() {
int pos = InterpolationSearch.interpolationSearch(myData, 19);
assertEquals(-1, pos);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/binarysearch/BinarySearch.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/binarysearch/BinarySearch.java | package com.baeldung.algorithms.binarysearch;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
public class BinarySearch {
public int runBinarySearchIteratively(int[] sortedArray, int key, int low, int high) {
int index = Integer.MAX_VALUE;
while (low <= high) {
int mid = low + ((high - low) / 2);
if (sortedArray[mid] < key) {
low = mid + 1;
} else if (sortedArray[mid] > key) {
high = mid - 1;
} else if (sortedArray[mid] == key) {
index = mid;
break;
}
}
return index;
}
public int runBinarySearchRecursively(int[] sortedArray, int key, int low, int high) {
int middle = low + ((high - low) / 2);
if (high < low) {
return -1;
}
if (key == sortedArray[middle]) {
return middle;
} else if (key < sortedArray[middle]) {
return runBinarySearchRecursively(sortedArray, key, low, middle - 1);
} else {
return runBinarySearchRecursively(sortedArray, key, middle + 1, high);
}
}
public int runBinarySearchUsingJavaArrays(int[] sortedArray, Integer key) {
int index = Arrays.binarySearch(sortedArray, key);
return index;
}
public int runBinarySearchUsingJavaCollections(List<Integer> sortedList, Integer key) {
int index = Collections.binarySearch(sortedList, key);
return index;
}
public List<Integer> runBinarySearchOnSortedArraysWithDuplicates(int[] sortedArray, Integer key) {
int startIndex = startIndexSearch(sortedArray, key);
int endIndex = endIndexSearch(sortedArray, key);
return IntStream.rangeClosed(startIndex, endIndex)
.boxed()
.collect(Collectors.toList());
}
private int endIndexSearch(int[] sortedArray, int target) {
int left = 0;
int right = sortedArray.length - 1;
int result = -1;
while (left <= right) {
int mid = left + (right - left) / 2;
if (sortedArray[mid] == target) {
result = mid;
left = mid + 1;
} else if (sortedArray[mid] < target) {
left = mid + 1;
} else {
right = mid - 1;
}
}
return result;
}
private int startIndexSearch(int[] sortedArray, int target) {
int left = 0;
int right = sortedArray.length - 1;
int result = -1;
while (left <= right) {
int mid = left + (right - left) / 2;
if (sortedArray[mid] == target) {
result = mid;
right = mid - 1;
} else if (sortedArray[mid] < target) {
left = mid + 1;
} else {
right = mid - 1;
}
}
return result;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/suffixtree/Node.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/suffixtree/Node.java | package com.baeldung.algorithms.suffixtree;
import java.util.ArrayList;
import java.util.List;
public class Node {
private String text;
private List<Node> children;
private int position;
public Node(String word, int position) {
this.text = word;
this.position = position;
this.children = new ArrayList<>();
}
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
public int getPosition() {
return position;
}
public void setPosition(int position) {
this.position = position;
}
public List<Node> getChildren() {
return children;
}
public void setChildren(List<Node> children) {
this.children = children;
}
public String printTree(String depthIndicator) {
String str = "";
String positionStr = position > -1 ? "[" + String.valueOf(position) + "]" : "";
str += depthIndicator + text + positionStr + "\n";
for (int i = 0; i < children.size(); i++) {
str += children.get(i)
.printTree(depthIndicator + "\t");
}
return str;
}
@Override
public String toString() {
return printTree("");
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/suffixtree/SuffixTree.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/suffixtree/SuffixTree.java | package com.baeldung.algorithms.suffixtree;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class SuffixTree {
private static final Logger LOGGER = LoggerFactory.getLogger(SuffixTree.class);
private static final String WORD_TERMINATION = "$";
private static final int POSITION_UNDEFINED = -1;
private Node root;
private String fullText;
public SuffixTree(String text) {
root = new Node("", POSITION_UNDEFINED);
for (int i = 0; i < text.length(); i++) {
addSuffix(text.substring(i) + WORD_TERMINATION, i);
}
fullText = text;
}
public List<String> searchText(String pattern) {
LOGGER.debug("Searching for pattern \"{}\"", pattern);
List<String> result = new ArrayList<>();
List<Node> nodes = getAllNodesInTraversePath(pattern, root, false);
if (nodes.size() > 0) {
Node lastNode = nodes.get(nodes.size() - 1);
if (lastNode != null) {
List<Integer> positions = getPositions(lastNode);
positions = positions.stream()
.sorted()
.collect(Collectors.toList());
positions.forEach(m -> result.add((markPatternInText(m, pattern))));
}
}
return result;
}
private void addSuffix(String suffix, int position) {
LOGGER.debug(">>>>>>>>>>>> Adding new suffix {}", suffix);
List<Node> nodes = getAllNodesInTraversePath(suffix, root, true);
if (nodes.size() == 0) {
addChildNode(root, suffix, position);
LOGGER.debug("{}", printTree());
} else {
Node lastNode = nodes.remove(nodes.size() - 1);
String newText = suffix;
if (nodes.size() > 0) {
String existingSuffixUptoLastNode = nodes.stream()
.map(a -> a.getText())
.reduce("", String::concat);
// Remove prefix from newText already included in parent
newText = newText.substring(existingSuffixUptoLastNode.length());
}
extendNode(lastNode, newText, position);
LOGGER.debug("{}", printTree());
}
}
private List<Integer> getPositions(Node node) {
List<Integer> positions = new ArrayList<>();
if (node.getText()
.endsWith(WORD_TERMINATION)) {
positions.add(node.getPosition());
}
for (int i = 0; i < node.getChildren()
.size(); i++) {
positions.addAll(getPositions(node.getChildren()
.get(i)));
}
return positions;
}
private String markPatternInText(Integer startPosition, String pattern) {
String matchingTextLHS = fullText.substring(0, startPosition);
String matchingText = fullText.substring(startPosition, startPosition + pattern.length());
String matchingTextRHS = fullText.substring(startPosition + pattern.length());
return matchingTextLHS + "[" + matchingText + "]" + matchingTextRHS;
}
private void addChildNode(Node parentNode, String text, int position) {
parentNode.getChildren()
.add(new Node(text, position));
}
private void extendNode(Node node, String newText, int position) {
String currentText = node.getText();
String commonPrefix = getLongestCommonPrefix(currentText, newText);
if (commonPrefix != currentText) {
String parentText = currentText.substring(0, commonPrefix.length());
String childText = currentText.substring(commonPrefix.length());
splitNodeToParentAndChild(node, parentText, childText);
}
String remainingText = newText.substring(commonPrefix.length());
addChildNode(node, remainingText, position);
}
private void splitNodeToParentAndChild(Node parentNode, String parentNewText, String childNewText) {
Node childNode = new Node(childNewText, parentNode.getPosition());
if (parentNode.getChildren()
.size() > 0) {
while (parentNode.getChildren()
.size() > 0) {
childNode.getChildren()
.add(parentNode.getChildren()
.remove(0));
}
}
parentNode.getChildren()
.add(childNode);
parentNode.setText(parentNewText);
parentNode.setPosition(POSITION_UNDEFINED);
}
private String getLongestCommonPrefix(String str1, String str2) {
int compareLength = Math.min(str1.length(), str2.length());
for (int i = 0; i < compareLength; i++) {
if (str1.charAt(i) != str2.charAt(i)) {
return str1.substring(0, i);
}
}
return str1.substring(0, compareLength);
}
private List<Node> getAllNodesInTraversePath(String pattern, Node startNode, boolean isAllowPartialMatch) {
List<Node> nodes = new ArrayList<>();
for (int i = 0; i < startNode.getChildren()
.size(); i++) {
Node currentNode = startNode.getChildren()
.get(i);
String nodeText = currentNode.getText();
if (pattern.charAt(0) == nodeText.charAt(0)) {
if (isAllowPartialMatch && pattern.length() <= nodeText.length()) {
nodes.add(currentNode);
return nodes;
}
int compareLength = Math.min(nodeText.length(), pattern.length());
for (int j = 1; j < compareLength; j++) {
if (pattern.charAt(j) != nodeText.charAt(j)) {
if (isAllowPartialMatch) {
nodes.add(currentNode);
}
return nodes;
}
}
nodes.add(currentNode);
if (pattern.length() > compareLength) {
List<Node> nodes2 = getAllNodesInTraversePath(pattern.substring(compareLength), currentNode, isAllowPartialMatch);
if (nodes2.size() > 0) {
nodes.addAll(nodes2);
} else if (!isAllowPartialMatch) {
nodes.add(null);
}
}
return nodes;
}
}
return nodes;
}
public String printTree() {
return root.printTree("");
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/breadthfirstsearch/Node.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/breadthfirstsearch/Node.java | package com.baeldung.algorithms.breadthfirstsearch;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
public class Node<T> {
private T value;
private Set<Node<T>> neighbors;
public Node(T value) {
this.value = value;
this.neighbors = new HashSet<>();
}
public T getValue() {
return value;
}
public Set<Node<T>> getNeighbors() {
return Collections.unmodifiableSet(neighbors);
}
public void connect(Node<T> node) {
if (this == node) throw new IllegalArgumentException("Can't connect node to itself");
this.neighbors.add(node);
node.neighbors.add(this);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/breadthfirstsearch/Tree.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/breadthfirstsearch/Tree.java | package com.baeldung.algorithms.breadthfirstsearch;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class Tree<T> {
private T value;
private List<Tree<T>> children;
private Tree(T value) {
this.value = value;
this.children = new ArrayList<>();
}
public static <T> Tree<T> of(T value) {
return new Tree<>(value);
}
public T getValue() {
return value;
}
public List<Tree<T>> getChildren() {
return Collections.unmodifiableList(children);
}
public Tree<T> addChild(T value) {
Tree<T> newChild = new Tree<>(value);
children.add(newChild);
return newChild;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/breadthfirstsearch/BreadthFirstSearchAlgorithm.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/breadthfirstsearch/BreadthFirstSearchAlgorithm.java | package com.baeldung.algorithms.breadthfirstsearch;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.*;
public class BreadthFirstSearchAlgorithm {
private static final Logger LOGGER = LoggerFactory.getLogger(BreadthFirstSearchAlgorithm.class);
public static <T> Optional<Tree<T>> search(T value, Tree<T> root) {
Queue<Tree<T>> queue = new ArrayDeque<>();
queue.add(root);
Tree<T> currentNode;
while (!queue.isEmpty()) {
currentNode = queue.remove();
LOGGER.debug("Visited node with value: {}", currentNode.getValue());
if (currentNode.getValue().equals(value)) {
return Optional.of(currentNode);
} else {
queue.addAll(currentNode.getChildren());
}
}
return Optional.empty();
}
public static <T> Optional<Node<T>> search(T value, Node<T> start) {
Queue<Node<T>> queue = new ArrayDeque<>();
queue.add(start);
Node<T> currentNode;
Set<Node<T>> alreadyVisited = new HashSet<>();
while (!queue.isEmpty()) {
currentNode = queue.remove();
LOGGER.debug("Visited node with value: {}", currentNode.getValue());
if (currentNode.getValue().equals(value)) {
return Optional.of(currentNode);
} else {
alreadyVisited.add(currentNode);
queue.addAll(currentNode.getNeighbors());
queue.removeAll(alreadyVisited);
}
}
return Optional.empty();
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/montecarlo/MonteCarloTreeSearch.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/montecarlo/MonteCarloTreeSearch.java | package com.baeldung.algorithms.mcts.montecarlo;
import java.util.List;
import com.baeldung.algorithms.mcts.tictactoe.Board;
import com.baeldung.algorithms.mcts.tree.Node;
import com.baeldung.algorithms.mcts.tree.Tree;
public class MonteCarloTreeSearch {
private static final int WIN_SCORE = 10;
private int level;
private int opponent;
public MonteCarloTreeSearch() {
this.level = 3;
}
public int getLevel() {
return level;
}
public void setLevel(int level) {
this.level = level;
}
private int getMillisForCurrentLevel() {
return 2 * (this.level - 1) + 1;
}
public Board findNextMove(Board board, int playerNo) {
long start = System.currentTimeMillis();
long end = start + 60 * getMillisForCurrentLevel();
opponent = 3 - playerNo;
Tree tree = new Tree();
Node rootNode = tree.getRoot();
rootNode.getState().setBoard(board);
rootNode.getState().setPlayerNo(opponent);
while (System.currentTimeMillis() < end) {
// Phase 1 - Selection
Node promisingNode = selectPromisingNode(rootNode);
// Phase 2 - Expansion
if (promisingNode.getState().getBoard().checkStatus() == Board.IN_PROGRESS)
expandNode(promisingNode);
// Phase 3 - Simulation
Node nodeToExplore = promisingNode;
if (promisingNode.getChildArray().size() > 0) {
nodeToExplore = promisingNode.getRandomChildNode();
}
int playoutResult = simulateRandomPlayout(nodeToExplore);
// Phase 4 - Update
backPropogation(nodeToExplore, playoutResult);
}
Node winnerNode = rootNode.getChildWithMaxScore();
tree.setRoot(winnerNode);
return winnerNode.getState().getBoard();
}
private Node selectPromisingNode(Node rootNode) {
Node node = rootNode;
while (node.getChildArray().size() != 0) {
node = UCT.findBestNodeWithUCT(node);
}
return node;
}
private void expandNode(Node node) {
List<State> possibleStates = node.getState().getAllPossibleStates();
possibleStates.forEach(state -> {
Node newNode = new Node(state);
newNode.setParent(node);
newNode.getState().setPlayerNo(node.getState().getOpponent());
node.getChildArray().add(newNode);
});
}
private void backPropogation(Node nodeToExplore, int playerNo) {
Node tempNode = nodeToExplore;
while (tempNode != null) {
tempNode.getState().incrementVisit();
if (tempNode.getState().getPlayerNo() == playerNo)
tempNode.getState().addScore(WIN_SCORE);
tempNode = tempNode.getParent();
}
}
private int simulateRandomPlayout(Node node) {
Node tempNode = new Node(node);
State tempState = tempNode.getState();
int boardStatus = tempState.getBoard().checkStatus();
if (boardStatus == opponent) {
tempNode.getParent().getState().setWinScore(Integer.MIN_VALUE);
return boardStatus;
}
while (boardStatus == Board.IN_PROGRESS) {
tempState.togglePlayer();
tempState.randomPlay();
boardStatus = tempState.getBoard().checkStatus();
}
return boardStatus;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/montecarlo/UCT.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/montecarlo/UCT.java | package com.baeldung.algorithms.mcts.montecarlo;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import com.baeldung.algorithms.mcts.tree.Node;
public class UCT {
public static double uctValue(int totalVisit, double nodeWinScore, int nodeVisit) {
if (nodeVisit == 0) {
return Integer.MAX_VALUE;
}
return (nodeWinScore / (double) nodeVisit) + 1.41 * Math.sqrt(Math.log(totalVisit) / (double) nodeVisit);
}
static Node findBestNodeWithUCT(Node node) {
int parentVisit = node.getState().getVisitCount();
return Collections.max(
node.getChildArray(),
Comparator.comparing(c -> uctValue(parentVisit, c.getState().getWinScore(), c.getState().getVisitCount())));
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/montecarlo/State.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/montecarlo/State.java | package com.baeldung.algorithms.mcts.montecarlo;
import java.util.ArrayList;
import java.util.List;
import com.baeldung.algorithms.mcts.tictactoe.Board;
import com.baeldung.algorithms.mcts.tictactoe.Position;
public class State {
private Board board;
private int playerNo;
private int visitCount;
private double winScore;
public State() {
board = new Board();
}
public State(State state) {
this.board = new Board(state.getBoard());
this.playerNo = state.getPlayerNo();
this.visitCount = state.getVisitCount();
this.winScore = state.getWinScore();
}
public State(Board board) {
this.board = new Board(board);
}
Board getBoard() {
return board;
}
void setBoard(Board board) {
this.board = board;
}
int getPlayerNo() {
return playerNo;
}
void setPlayerNo(int playerNo) {
this.playerNo = playerNo;
}
int getOpponent() {
return 3 - playerNo;
}
public int getVisitCount() {
return visitCount;
}
public void setVisitCount(int visitCount) {
this.visitCount = visitCount;
}
double getWinScore() {
return winScore;
}
void setWinScore(double winScore) {
this.winScore = winScore;
}
public List<State> getAllPossibleStates() {
List<State> possibleStates = new ArrayList<>();
List<Position> availablePositions = this.board.getEmptyPositions();
availablePositions.forEach(p -> {
State newState = new State(this.board);
newState.setPlayerNo(3 - this.playerNo);
newState.getBoard().performMove(newState.getPlayerNo(), p);
possibleStates.add(newState);
});
return possibleStates;
}
void incrementVisit() {
this.visitCount++;
}
void addScore(double score) {
if (this.winScore != Integer.MIN_VALUE)
this.winScore += score;
}
void randomPlay() {
List<Position> availablePositions = this.board.getEmptyPositions();
int totalPossibilities = availablePositions.size();
int selectRandom = (int) (Math.random() * totalPossibilities);
this.board.performMove(this.playerNo, availablePositions.get(selectRandom));
}
void togglePlayer() {
this.playerNo = 3 - this.playerNo;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/tictactoe/Board.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/tictactoe/Board.java | package com.baeldung.algorithms.mcts.tictactoe;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class Board {
int[][] boardValues;
int totalMoves;
public static final int DEFAULT_BOARD_SIZE = 3;
public static final int IN_PROGRESS = -1;
public static final int DRAW = 0;
public static final int P1 = 1;
public static final int P2 = 2;
public Board() {
boardValues = new int[DEFAULT_BOARD_SIZE][DEFAULT_BOARD_SIZE];
}
public Board(int boardSize) {
boardValues = new int[boardSize][boardSize];
}
public Board(int[][] boardValues) {
this.boardValues = boardValues;
}
public Board(int[][] boardValues, int totalMoves) {
this.boardValues = boardValues;
this.totalMoves = totalMoves;
}
public Board(Board board) {
int boardLength = board.getBoardValues().length;
this.boardValues = new int[boardLength][boardLength];
int[][] boardValues = board.getBoardValues();
int n = boardValues.length;
for (int i = 0; i < n; i++) {
int m = boardValues[i].length;
for (int j = 0; j < m; j++) {
this.boardValues[i][j] = boardValues[i][j];
}
}
}
public void performMove(int player, Position p) {
this.totalMoves++;
boardValues[p.getX()][p.getY()] = player;
}
public int[][] getBoardValues() {
return boardValues;
}
public void setBoardValues(int[][] boardValues) {
this.boardValues = boardValues;
}
public int checkStatus() {
int boardSize = boardValues.length;
int maxIndex = boardSize - 1;
int[] diag1 = new int[boardSize];
int[] diag2 = new int[boardSize];
for (int i = 0; i < boardSize; i++) {
int[] row = boardValues[i];
int[] col = new int[boardSize];
for (int j = 0; j < boardSize; j++) {
col[j] = boardValues[j][i];
}
int checkRowForWin = checkForWin(row);
if(checkRowForWin!=0)
return checkRowForWin;
int checkColForWin = checkForWin(col);
if(checkColForWin!=0)
return checkColForWin;
diag1[i] = boardValues[i][i];
diag2[i] = boardValues[maxIndex - i][i];
}
int checkDia1gForWin = checkForWin(diag1);
if(checkDia1gForWin!=0)
return checkDia1gForWin;
int checkDiag2ForWin = checkForWin(diag2);
if(checkDiag2ForWin!=0)
return checkDiag2ForWin;
if (getEmptyPositions().size() > 0)
return IN_PROGRESS;
else
return DRAW;
}
private int checkForWin(int[] row) {
boolean isEqual = true;
int size = row.length;
int previous = row[0];
for (int i = 0; i < size; i++) {
if (previous != row[i]) {
isEqual = false;
break;
}
previous = row[i];
}
if(isEqual)
return previous;
else
return 0;
}
public void printBoard() {
int size = this.boardValues.length;
for (int i = 0; i < size; i++) {
for (int j = 0; j < size; j++) {
System.out.print(boardValues[i][j] + " ");
}
System.out.println();
}
}
public List<Position> getEmptyPositions() {
int size = this.boardValues.length;
List<Position> emptyPositions = new ArrayList<>();
for (int i = 0; i < size; i++) {
for (int j = 0; j < size; j++) {
if (boardValues[i][j] == 0)
emptyPositions.add(new Position(i, j));
}
}
return emptyPositions;
}
public void printStatus() {
switch (this.checkStatus()) {
case P1:
System.out.println("Player 1 wins");
break;
case P2:
System.out.println("Player 2 wins");
break;
case DRAW:
System.out.println("Game Draw");
break;
case IN_PROGRESS:
System.out.println("Game In Progress");
break;
}
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/tictactoe/Position.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/tictactoe/Position.java | package com.baeldung.algorithms.mcts.tictactoe;
public class Position {
int x;
int y;
public Position() {
}
public Position(int x, int y) {
this.x = x;
this.y = y;
}
public int getX() {
return x;
}
public void setX(int x) {
this.x = x;
}
public int getY() {
return y;
}
public void setY(int y) {
this.y = y;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/tree/Node.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/tree/Node.java | package com.baeldung.algorithms.mcts.tree;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import com.baeldung.algorithms.mcts.montecarlo.State;
public class Node {
State state;
Node parent;
List<Node> childArray;
public Node() {
this.state = new State();
childArray = new ArrayList<>();
}
public Node(State state) {
this.state = state;
childArray = new ArrayList<>();
}
public Node(State state, Node parent, List<Node> childArray) {
this.state = state;
this.parent = parent;
this.childArray = childArray;
}
public Node(Node node) {
this.childArray = new ArrayList<>();
this.state = new State(node.getState());
if (node.getParent() != null)
this.parent = node.getParent();
List<Node> childArray = node.getChildArray();
for (Node child : childArray) {
this.childArray.add(new Node(child));
}
}
public State getState() {
return state;
}
public void setState(State state) {
this.state = state;
}
public Node getParent() {
return parent;
}
public void setParent(Node parent) {
this.parent = parent;
}
public List<Node> getChildArray() {
return childArray;
}
public void setChildArray(List<Node> childArray) {
this.childArray = childArray;
}
public Node getRandomChildNode() {
int noOfPossibleMoves = this.childArray.size();
int selectRandom = (int) (Math.random() * noOfPossibleMoves);
return this.childArray.get(selectRandom);
}
public Node getChildWithMaxScore() {
return Collections.max(this.childArray, Comparator.comparing(c -> {
return c.getState().getVisitCount();
}));
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/tree/Tree.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/mcts/tree/Tree.java | package com.baeldung.algorithms.mcts.tree;
public class Tree {
Node root;
public Tree() {
root = new Node();
}
public Tree(Node root) {
this.root = root;
}
public Node getRoot() {
return root;
}
public void setRoot(Node root) {
this.root = root;
}
public void addChild(Node parent, Node child) {
parent.getChildArray().add(child);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/dfs/Graph.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/dfs/Graph.java | package com.baeldung.algorithms.dfs;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Stack;
public class Graph {
private Map<Integer, List<Integer>> adjVertices;
public Graph() {
this.adjVertices = new HashMap<Integer, List<Integer>>();
}
public void addVertex(int vertex) {
adjVertices.putIfAbsent(vertex, new ArrayList<>());
}
public void addEdge(int src, int dest) {
adjVertices.get(src).add(dest);
}
public boolean[] dfsWithoutRecursion(int start) {
Stack<Integer> stack = new Stack<Integer>();
boolean[] isVisited = new boolean[adjVertices.size()];
stack.push(start);
while (!stack.isEmpty()) {
int current = stack.pop();
if(!isVisited[current]){
isVisited[current] = true;
visit(current);
for (int dest : adjVertices.get(current)) {
if (!isVisited[dest])
stack.push(dest);
}
}
}
return isVisited;
}
public boolean[] dfs(int start) {
boolean[] isVisited = new boolean[adjVertices.size()];
return dfsRecursive(start, isVisited);
}
private boolean[] dfsRecursive(int current, boolean[] isVisited) {
isVisited[current] = true;
visit(current);
for (int dest : adjVertices.get(current)) {
if (!isVisited[dest])
dfsRecursive(dest, isVisited);
}
return isVisited;
}
public List<Integer> topologicalSort(int start) {
LinkedList<Integer> result = new LinkedList<Integer>();
boolean[] isVisited = new boolean[adjVertices.size()];
topologicalSortRecursive(start, isVisited, result);
return result;
}
private void topologicalSortRecursive(int current, boolean[] isVisited, LinkedList<Integer> result) {
isVisited[current] = true;
for (int dest : adjVertices.get(current)) {
if (!isVisited[dest])
topologicalSortRecursive(dest, isVisited, result);
}
result.addFirst(current);
}
private void visit(int value) {
System.out.print(" " + value);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/dfs/BinaryTree.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/dfs/BinaryTree.java | package com.baeldung.algorithms.dfs;
import java.util.Stack;
public class BinaryTree {
Node root;
public void add(int value) {
root = addRecursive(root, value);
}
private Node addRecursive(Node current, int value) {
if (current == null) {
return new Node(value);
}
if (value < current.value) {
current.left = addRecursive(current.left, value);
} else if (value > current.value) {
current.right = addRecursive(current.right, value);
}
return current;
}
public boolean isEmpty() {
return root == null;
}
public int getSize() {
return getSizeRecursive(root);
}
private int getSizeRecursive(Node current) {
return current == null ? 0 : getSizeRecursive(current.left) + 1 + getSizeRecursive(current.right);
}
public boolean containsNode(int value) {
return containsNodeRecursive(root, value);
}
private boolean containsNodeRecursive(Node current, int value) {
if (current == null) {
return false;
}
if (value == current.value) {
return true;
}
return value < current.value
? containsNodeRecursive(current.left, value)
: containsNodeRecursive(current.right, value);
}
public void delete(int value) {
root = deleteRecursive(root, value);
}
private Node deleteRecursive(Node current, int value) {
if (current == null) {
return null;
}
if (value == current.value) {
// Case 1: no children
if (current.left == null && current.right == null) {
return null;
}
// Case 2: only 1 child
if (current.right == null) {
return current.left;
}
if (current.left == null) {
return current.right;
}
// Case 3: 2 children
int smallestValue = findSmallestValue(current.right);
current.value = smallestValue;
current.right = deleteRecursive(current.right, smallestValue);
return current;
}
if (value < current.value) {
current.left = deleteRecursive(current.left, value);
return current;
}
current.right = deleteRecursive(current.right, value);
return current;
}
private int findSmallestValue(Node root) {
return root.left == null ? root.value : findSmallestValue(root.left);
}
public void traverseInOrder(Node node) {
if (node != null) {
traverseInOrder(node.left);
visit(node.value);
traverseInOrder(node.right);
}
}
public void traversePreOrder(Node node) {
if (node != null) {
visit(node.value);
traversePreOrder(node.left);
traversePreOrder(node.right);
}
}
public void traversePostOrder(Node node) {
if (node != null) {
traversePostOrder(node.left);
traversePostOrder(node.right);
visit(node.value);
}
}
public void traverseInOrderWithoutRecursion() {
Stack<Node> stack = new Stack<>();
Node current = root;
while (current != null || !stack.isEmpty()) {
while (current != null) {
stack.push(current);
current = current.left;
}
Node top = stack.pop();
visit(top.value);
current = top.right;
}
}
public void traversePreOrderWithoutRecursion() {
Stack<Node> stack = new Stack<>();
Node current;
stack.push(root);
while(! stack.isEmpty()) {
current = stack.pop();
visit(current.value);
if(current.right != null)
stack.push(current.right);
if(current.left != null)
stack.push(current.left);
}
}
public void traversePostOrderWithoutRecursion() {
Stack<Node> stack = new Stack<>();
Node prev = root;
Node current;
stack.push(root);
while (!stack.isEmpty()) {
current = stack.peek();
boolean hasChild = (current.left != null || current.right != null);
boolean isPrevLastChild = (prev == current.right || (prev == current.left && current.right == null));
if (!hasChild || isPrevLastChild) {
current = stack.pop();
visit(current.value);
prev = current;
} else {
if (current.right != null) {
stack.push(current.right);
}
if (current.left != null) {
stack.push(current.left);
}
}
}
}
private void visit(int value) {
System.out.print(" " + value);
}
static class Node {
int value;
Node left;
Node right;
Node(int value) {
this.value = value;
right = null;
left = null;
}
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/kthsmallest/KthSmallest.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/kthsmallest/KthSmallest.java | package com.baeldung.algorithms.kthsmallest;
import java.util.Arrays;
import java.util.NoSuchElementException;
import static java.lang.Math.max;
import static java.lang.Math.min;
public class KthSmallest {
public static int findKthSmallestElement(int k, int[] list1, int[] list2) throws NoSuchElementException, IllegalArgumentException {
checkInput(k, list1, list2);
// we are looking for the minimum value
if(k == 1) {
return min(list1[0], list2[0]);
}
// we are looking for the maximum value
if(list1.length + list2.length == k) {
return max(list1[list1.length-1], list2[list2.length-1]);
}
// swap lists if needed to make sure we take at least one element from list1
if(k <= list2.length && list2[k-1] < list1[0]) {
int[] list1_ = list1;
list1 = list2;
list2 = list1_;
}
// correct left boundary if k is bigger than the size of list2
int left = k < list2.length ? 0 : k - list2.length - 1;
// the inital right boundary cannot exceed the list1
int right = min(k-1, list1.length - 1);
int nElementsList1, nElementsList2;
// binary search
do {
nElementsList1 = ((left + right) / 2) + 1;
nElementsList2 = k - nElementsList1;
if(nElementsList2 > 0) {
if (list1[nElementsList1 - 1] > list2[nElementsList2 - 1]) {
right = nElementsList1 - 2;
} else {
left = nElementsList1;
}
}
} while(!kthSmallesElementFound(list1, list2, nElementsList1, nElementsList2));
return nElementsList2 == 0 ? list1[nElementsList1-1] : max(list1[nElementsList1-1], list2[nElementsList2-1]);
}
private static boolean kthSmallesElementFound(int[] list1, int[] list2, int nElementsList1, int nElementsList2) {
// we do not take any element from the second list
if(nElementsList2 < 1) {
return true;
}
if(list1[nElementsList1-1] == list2[nElementsList2-1]) {
return true;
}
if(nElementsList1 == list1.length) {
return list1[nElementsList1-1] <= list2[nElementsList2];
}
if(nElementsList2 == list2.length) {
return list2[nElementsList2-1] <= list1[nElementsList1];
}
return list1[nElementsList1-1] <= list2[nElementsList2] && list2[nElementsList2-1] <= list1[nElementsList1];
}
private static void checkInput(int k, int[] list1, int[] list2) throws NoSuchElementException, IllegalArgumentException {
if(list1 == null || list2 == null || k < 1) {
throw new IllegalArgumentException();
}
if(list1.length == 0 || list2.length == 0) {
throw new IllegalArgumentException();
}
if(k > list1.length + list2.length) {
throw new NoSuchElementException();
}
}
public static int getKthElementSorted(int[] list1, int[] list2, int k) {
int length1 = list1.length, length2 = list2.length;
int[] combinedArray = new int[length1 + length2];
System.arraycopy(list1, 0, combinedArray, 0, list1.length);
System.arraycopy(list2, 0, combinedArray, list1.length, list2.length);
Arrays.sort(combinedArray);
return combinedArray[k-1];
}
public static int getKthElementMerge(int[] list1, int[] list2, int k) {
int i1 = 0, i2 = 0;
while(i1 < list1.length && i2 < list2.length && (i1 + i2) < k) {
if(list1[i1] < list2[i2]) {
i1++;
} else {
i2++;
}
}
if((i1 + i2) < k) {
return i1 < list1.length ? list1[k - i2 - 1] : list2[k - i1 - 1];
} else if(i1 > 0 && i2 > 0) {
return Math.max(list1[i1-1], list2[i2-1]);
} else {
return i1 == 0 ? list2[i2-1] : list1[i1-1];
}
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/firstnonrepeating/FirstNonRepeatingElement.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/firstnonrepeating/FirstNonRepeatingElement.java | package com.baeldung.algorithms.firstnonrepeating;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class FirstNonRepeatingElement {
public static Integer findFirstNonRepeatingUsingForLoop(List<Integer> list) {
for (int i = 0; i < list.size(); i++) {
int current = list.get(i);
boolean isRepeating = false;
for (int j = 0; j < list.size(); j++) {
if (i != j && current == list.get(j)) {
isRepeating = true;
break;
}
}
if (!isRepeating) {
return current;
}
}
return null;
}
public static Integer findFirstNonRepeatedElementUsingIndex(List<Integer> list) {
for (int i = 0; i < list.size(); i++) {
if (list.indexOf(list.get(i)) == list.lastIndexOf(list.get(i))) {
return list.get(i);
}
}
return null;
}
public static Integer findFirstNonRepeatingUsingHashMap(List<Integer> list) {
Map<Integer, Integer> counts = new HashMap<>();
for (int num : list) {
counts.put(num, counts.getOrDefault(num, 0) + 1);
}
for (int num : list) {
if (counts.get(num) == 1) {
return num;
}
}
return null;
}
public static Integer findFirstNonRepeatingUsingArray(List<Integer> list) {
int maxElement = Collections.max(list);
int[] frequency = new int[maxElement + 1];
for (int num : list) {
frequency[num]++;
}
for (int num : list) {
if (frequency[num] == 1) {
return num;
}
}
return null;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/quadtree/Region.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/quadtree/Region.java | package com.baeldung.algorithms.quadtree;
public class Region {
private float x1;
private float y1;
private float x2;
private float y2;
public Region(float x1, float y1, float x2, float y2) {
if (x1 >= x2 || y1 >= y2)
throw new IllegalArgumentException("(x1,y1) should be lesser than (x2,y2)");
this.x1 = x1;
this.y1 = y1;
this.x2 = x2;
this.y2 = y2;
}
public Region getQuadrant(int quadrantIndex) {
float quadrantWidth = (this.x2 - this.x1) / 2;
float quadrantHeight = (this.y2 - this.y1) / 2;
// 0=SW, 1=NW, 2=NE, 3=SE
switch (quadrantIndex) {
case 0:
return new Region(x1, y1, x1 + quadrantWidth, y1 + quadrantHeight);
case 1:
return new Region(x1, y1 + quadrantHeight, x1 + quadrantWidth, y2);
case 2:
return new Region(x1 + quadrantWidth, y1 + quadrantHeight, x2, y2);
case 3:
return new Region(x1 + quadrantWidth, y1, x2, y1 + quadrantHeight);
}
return null;
}
public boolean containsPoint(Point point) {
// Consider left and top side to be inclusive for points on border
return point.getX() >= this.x1
&& point.getX() < this.x2
&& point.getY() >= this.y1
&& point.getY() < this.y2;
}
public boolean doesOverlap(Region testRegion) {
// Is test region completely to left of my region?
if (testRegion.getX2() < this.getX1()) {
return false;
}
// Is test region completely to right of my region?
if (testRegion.getX1() > this.getX2()) {
return false;
}
// Is test region completely above my region?
if (testRegion.getY1() > this.getY2()) {
return false;
}
// Is test region completely below my region?
if (testRegion.getY2() < this.getY1()) {
return false;
}
return true;
}
@Override
public String toString() {
return "[Region (x1=" + x1 + ", y1=" + y1 + "), (x2=" + x2 + ", y2=" + y2 + ")]";
}
public float getX1() {
return x1;
}
public float getY1() {
return y1;
}
public float getX2() {
return x2;
}
public float getY2() {
return y2;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/quadtree/Point.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/quadtree/Point.java | package com.baeldung.algorithms.quadtree;
public class Point {
private float x;
private float y;
public Point(float x, float y) {
this.x = x;
this.y = y;
}
public float getX() {
return x;
}
public float getY() {
return y;
}
@Override
public String toString() {
return "[" + x + " , " + y + "]";
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/quadtree/QuadTree.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/quadtree/QuadTree.java | package com.baeldung.algorithms.quadtree;
import java.util.ArrayList;
import java.util.List;
public class QuadTree {
private static final int MAX_POINTS = 3;
private Region area;
private List<Point> points = new ArrayList<>();
private List<QuadTree> quadTrees = new ArrayList<>();
private StringBuilder searchTraversePath;
public QuadTree(Region area) {
this.area = area;
}
public boolean addPoint(Point point) {
if (this.area.containsPoint(point)) {
if (this.points.size() < MAX_POINTS) {
this.points.add(point);
return true;
} else {
if (this.quadTrees.size() == 0) {
createQuadrants();
}
return addPointToOneQuadrant(point);
}
}
return false;
}
private boolean addPointToOneQuadrant(Point point) {
boolean isPointAdded;
for (int i = 0; i < 4; i++) {
isPointAdded = this.quadTrees.get(i)
.addPoint(point);
if (isPointAdded)
return true;
}
return false;
}
private void createQuadrants() {
Region region;
for (int i = 0; i < 4; i++) {
region = this.area.getQuadrant(i);
quadTrees.add(new QuadTree(region));
}
}
public List<Point> search(Region searchRegion, List<Point> matches, String depthIndicator) {
searchTraversePath = new StringBuilder();
if (matches == null) {
matches = new ArrayList<Point>();
searchTraversePath.append(depthIndicator)
.append("Search Boundary =")
.append(searchRegion)
.append("\n");
}
if (!this.area.doesOverlap(searchRegion)) {
return matches;
} else {
for (Point point : points) {
if (searchRegion.containsPoint(point)) {
searchTraversePath.append(depthIndicator)
.append("Found match " + point)
.append("\n");
matches.add(point);
}
}
if (this.quadTrees.size() > 0) {
for (int i = 0; i < 4; i++) {
searchTraversePath.append(depthIndicator)
.append("Q")
.append(i)
.append("-->")
.append(quadTrees.get(i).area)
.append("\n");
quadTrees.get(i)
.search(searchRegion, matches, depthIndicator + "\t");
this.searchTraversePath.append(quadTrees.get(i)
.printSearchTraversePath());
}
}
}
return matches;
}
public String printTree(String depthIndicator) {
String str = "";
if (depthIndicator == "") {
str += "Root-->" + area.toString() + "\n";
}
for (Point point : points) {
str += depthIndicator + point.toString() + "\n";
}
for (int i = 0; i < quadTrees.size(); i++) {
str += depthIndicator + "Q" + String.valueOf(i) + "-->" + quadTrees.get(i).area.toString() + "\n";
str += quadTrees.get(i)
.printTree(depthIndicator + "\t");
}
return str;
}
public String printSearchTraversePath() {
return searchTraversePath.toString();
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/textsearch/TextSearchAlgorithms.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/textsearch/TextSearchAlgorithms.java | package com.baeldung.algorithms.textsearch;
import java.math.BigInteger;
import java.util.Random;
public class TextSearchAlgorithms {
public static long getBiggerPrime(int m) {
BigInteger prime = BigInteger.probablePrime(getNumberOfBits(m) + 1, new Random());
return prime.longValue();
}
public static long getLowerPrime(long number) {
BigInteger prime = BigInteger.probablePrime(getNumberOfBits(number) - 1, new Random());
return prime.longValue();
}
private static int getNumberOfBits(final int number) {
return Integer.SIZE - Integer.numberOfLeadingZeros(number);
}
private static int getNumberOfBits(final long number) {
return Long.SIZE - Long.numberOfLeadingZeros(number);
}
public static int simpleTextSearch(char[] pattern, char[] text) {
int patternSize = pattern.length;
int textSize = text.length;
int i = 0;
while ((i + patternSize) <= textSize) {
int j = 0;
while (text[i + j] == pattern[j]) {
j += 1;
if (j >= patternSize)
return i;
}
i += 1;
}
return -1;
}
public static int RabinKarpMethod(char[] pattern, char[] text) {
int patternSize = pattern.length; // m
int textSize = text.length; // n
long prime = getBiggerPrime(patternSize);
long r = 1;
for (int i = 0; i < patternSize - 1; i++) {
r *= 2;
r = r % prime;
}
long[] t = new long[textSize];
t[0] = 0;
long pfinger = 0;
for (int j = 0; j < patternSize; j++) {
t[0] = (2 * t[0] + text[j]) % prime;
pfinger = (2 * pfinger + pattern[j]) % prime;
}
int i = 0;
boolean passed = false;
int diff = textSize - patternSize;
for (i = 0; i <= diff; i++) {
if (t[i] == pfinger) {
passed = true;
for (int k = 0; k < patternSize; k++) {
if (text[i + k] != pattern[k]) {
passed = false;
break;
}
}
if (passed) {
return i;
}
}
if (i < diff) {
long value = 2 * (t[i] - r * text[i]) + text[i + patternSize];
t[i + 1] = ((value % prime) + prime) % prime;
}
}
return -1;
}
public static int KnuthMorrisPrattSearch(char[] pattern, char[] text) {
int patternSize = pattern.length; // m
int textSize = text.length; // n
int i = 0, j = 0;
int[] shift = KnuthMorrisPrattShift(pattern);
while ((i + patternSize) <= textSize) {
while (text[i + j] == pattern[j]) {
j += 1;
if (j >= patternSize)
return i;
}
if (j > 0) {
i += shift[j - 1];
j = Math.max(j - shift[j - 1], 0);
} else {
i++;
j = 0;
}
}
return -1;
}
public static int[] KnuthMorrisPrattShift(char[] pattern) {
int patternSize = pattern.length;
int[] shift = new int[patternSize];
shift[0] = 1;
int i = 1, j = 0;
while ((i + j) < patternSize) {
if (pattern[i + j] == pattern[j]) {
shift[i + j] = i;
j++;
} else {
if (j == 0)
shift[i] = i + 1;
if (j > 0) {
i = i + shift[j - 1];
j = Math.max(j - shift[j - 1], 0);
} else {
i = i + 1;
j = 0;
}
}
}
return shift;
}
public static int BoyerMooreHorspoolSimpleSearch(char[] pattern, char[] text) {
int patternSize = pattern.length;
int textSize = text.length;
int i = 0, j = 0;
while ((i + patternSize) <= textSize) {
j = patternSize - 1;
while (text[i + j] == pattern[j]) {
j--;
if (j < 0)
return i;
}
i++;
}
return -1;
}
public static int BoyerMooreHorspoolSearch(char[] pattern, char[] text) {
int shift[] = new int[256];
for (int k = 0; k < 256; k++) {
shift[k] = pattern.length;
}
for (int k = 0; k < pattern.length - 1; k++) {
shift[pattern[k]] = pattern.length - 1 - k;
}
int i = 0, j = 0;
while ((i + pattern.length) <= text.length) {
j = pattern.length - 1;
while (text[i + j] == pattern[j]) {
j -= 1;
if (j < 0)
return i;
}
i = i + shift[text[i + pattern.length - 1]];
}
return -1;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/interpolationsearch/InterpolationSearch.java | algorithms-modules/algorithms-searching/src/main/java/com/baeldung/algorithms/interpolationsearch/InterpolationSearch.java | package com.baeldung.algorithms.interpolationsearch;
public class InterpolationSearch {
public static int interpolationSearch(int[] data, int item) {
int highEnd = (data.length - 1);
int lowEnd = 0;
while (item >= data[lowEnd] && item <= data[highEnd] && lowEnd <= highEnd) {
int probe = lowEnd + (highEnd - lowEnd) * (item - data[lowEnd]) / (data[highEnd] - data[lowEnd]);
if (highEnd == lowEnd) {
if (data[lowEnd] == item) {
return lowEnd;
} else {
return -1;
}
}
if (data[probe] == item) {
return probe;
}
if (data[probe] < item) {
lowEnd = probe + 1;
} else {
highEnd = probe - 1;
}
}
return -1;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/kruskal/KruskalUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/kruskal/KruskalUnitTest.java | package com.baeldung.algorithms.kruskal;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertTrue;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import com.google.common.graph.MutableValueGraph;
import com.google.common.graph.ValueGraph;
import com.google.common.graph.ValueGraphBuilder;
import com.baeldung.algorithms.kruskal.Kruskal;
class KruskalUnitTest {
private MutableValueGraph<Integer, Double> graph;
@BeforeEach
public void setup() {
graph = ValueGraphBuilder.undirected().build();
graph.putEdgeValue(0, 1, 8.0);
graph.putEdgeValue(0, 2, 5.0);
graph.putEdgeValue(1, 2, 9.0);
graph.putEdgeValue(1, 3, 11.0);
graph.putEdgeValue(2, 3, 15.0);
graph.putEdgeValue(2, 4, 10.0);
graph.putEdgeValue(3, 4, 7.0);
}
@Test
void givenGraph_whenMinimumSpanningTree_thenOutputCorrectResult() {
final Kruskal kruskal = new Kruskal();
ValueGraph<Integer, Double> spanningTree = kruskal.minSpanningTree(graph);
assertTrue(spanningTree.hasEdgeConnecting(0, 1));
assertTrue(spanningTree.hasEdgeConnecting(0, 2));
assertTrue(spanningTree.hasEdgeConnecting(2, 4));
assertTrue(spanningTree.hasEdgeConnecting(3, 4));
assertEquals(graph.edgeValue(0, 1), spanningTree.edgeValue(0, 1));
assertEquals(graph.edgeValue(0, 2), spanningTree.edgeValue(0, 2));
assertEquals(graph.edgeValue(2, 4), spanningTree.edgeValue(2, 4));
assertEquals(graph.edgeValue(3, 4), spanningTree.edgeValue(3, 4));
assertFalse(spanningTree.hasEdgeConnecting(1, 2));
assertFalse(spanningTree.hasEdgeConnecting(1, 3));
assertFalse(spanningTree.hasEdgeConnecting(2, 3));
}
@Test
void givenGraph_whenMaximumSpanningTree_thenOutputCorrectResult() {
final Kruskal kruskal = new Kruskal();
ValueGraph<Integer, Double> spanningTree = kruskal.maxSpanningTree(graph);
assertTrue(spanningTree.hasEdgeConnecting(0, 1));
assertTrue(spanningTree.hasEdgeConnecting(1, 3));
assertTrue(spanningTree.hasEdgeConnecting(2, 3));
assertTrue(spanningTree.hasEdgeConnecting(2, 4));
assertEquals(graph.edgeValue(0, 1), spanningTree.edgeValue(0, 1));
assertEquals(graph.edgeValue(1, 3), spanningTree.edgeValue(1, 3));
assertEquals(graph.edgeValue(2, 3), spanningTree.edgeValue(2, 3));
assertEquals(graph.edgeValue(2, 4), spanningTree.edgeValue(2, 4));
assertFalse(spanningTree.hasEdgeConnecting(0, 2));
assertFalse(spanningTree.hasEdgeConnecting(1, 2));
assertFalse(spanningTree.hasEdgeConnecting(3, 4));
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/boruvka/BoruvkaUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/boruvka/BoruvkaUnitTest.java | package com.baeldung.algorithms.boruvka;
import static org.junit.jupiter.api.Assertions.assertEquals;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import com.google.common.graph.MutableValueGraph;
import com.google.common.graph.ValueGraphBuilder;
class BoruvkaUnitTest {
private MutableValueGraph<Integer, Integer> graph;
@BeforeEach
public void setup() {
graph = ValueGraphBuilder.undirected()
.build();
graph.putEdgeValue(0, 1, 8);
graph.putEdgeValue(0, 2, 5);
graph.putEdgeValue(1, 2, 9);
graph.putEdgeValue(1, 3, 11);
graph.putEdgeValue(2, 3, 15);
graph.putEdgeValue(2, 4, 10);
graph.putEdgeValue(3, 4, 7);
}
@Test
void givenInputGraph_whenBoruvkaPerformed_thenMinimumSpanningTree() {
BoruvkaMST boruvkaMST = new BoruvkaMST(graph);
MutableValueGraph<Integer, Integer> mst = boruvkaMST.getMST();
assertEquals(30, boruvkaMST.getTotalWeight());
assertEquals(4, mst.edges().size());
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/linkedlist/LinkedListReversalUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/linkedlist/LinkedListReversalUnitTest.java | package com.baeldung.algorithms.linkedlist;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import org.junit.jupiter.api.Test;
class LinkedListReversalUnitTest {
@Test
void givenLinkedList_whenIterativeReverse_thenOutputCorrectResult() {
ListNode head = constructLinkedList();
ListNode node = head;
for (int i = 1; i <= 5; i++) {
assertNotNull(node);
assertEquals(i, node.getData());
node = node.getNext();
}
LinkedListReversal reversal = new LinkedListReversal();
node = reversal.reverseList(head);
for (int i = 5; i >= 1; i--) {
assertNotNull(node);
assertEquals(i, node.getData());
node = node.getNext();
}
}
@Test
void givenLinkedList_whenRecursiveReverse_thenOutputCorrectResult() {
ListNode head = constructLinkedList();
ListNode node = head;
for (int i = 1; i <= 5; i++) {
assertNotNull(node);
assertEquals(i, node.getData());
node = node.getNext();
}
LinkedListReversal reversal = new LinkedListReversal();
node = reversal.reverseListRecursive(head);
for (int i = 5; i >= 1; i--) {
assertNotNull(node);
assertEquals(i, node.getData());
node = node.getNext();
}
}
private ListNode constructLinkedList() {
ListNode head = null;
ListNode tail = null;
for (int i = 1; i <= 5; i++) {
ListNode node = new ListNode(i);
if (head == null) {
head = node;
} else {
tail.setNext(node);
}
tail = node;
}
return head;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/minheapmerge/MinHeapUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/minheapmerge/MinHeapUnitTest.java | package com.baeldung.algorithms.minheapmerge;
import static org.hamcrest.CoreMatchers.equalTo;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.MatcherAssert.assertThat;
import org.junit.jupiter.api.Test;
class MinHeapUnitTest {
private final int[][] inputArray = { { 0, 6 }, { 1, 5, 10, 100 }, { 2, 4, 200, 650 } };
private final int[] expectedArray = { 0, 1, 2, 4, 5, 6, 10, 100, 200, 650 };
@Test
void givenSortedArrays_whenMerged_thenShouldReturnASingleSortedarray() {
int[] resultArray = MinHeap.merge(inputArray);
assertThat(resultArray.length, is(equalTo(10)));
assertThat(resultArray, is(equalTo(expectedArray)));
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/caesarcipher/CaesarCipherUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/caesarcipher/CaesarCipherUnitTest.java | package com.baeldung.algorithms.caesarcipher;
import org.junit.jupiter.api.Test;
import static org.assertj.core.api.Assertions.assertThat;
class CaesarCipherUnitTest {
private static final String SENTENCE = "he told me i could never teach a llama to drive";
private static final String SENTENCE_SHIFTED_THREE = "kh wrog ph l frxog qhyhu whdfk d oodpd wr gulyh";
private static final String SENTENCE_SHIFTED_TEN = "ro dyvn wo s myevn xofob dokmr k vvkwk dy nbsfo";
private CaesarCipher algorithm = new CaesarCipher();
@Test
void givenSentenceAndShiftThree_whenCipher_thenCipheredMessageWithoutOverflow() {
String cipheredSentence = algorithm.cipher(SENTENCE, 3);
assertThat(cipheredSentence)
.isEqualTo(SENTENCE_SHIFTED_THREE);
}
@Test
void givenSentenceAndShiftTen_whenCipher_thenCipheredMessageWithOverflow() {
String cipheredSentence = algorithm.cipher(SENTENCE, 10);
assertThat(cipheredSentence)
.isEqualTo(SENTENCE_SHIFTED_TEN);
}
@Test
void givenSentenceAndShiftThirtySix_whenCipher_thenCipheredLikeTenMessageWithOverflow() {
String cipheredSentence = algorithm.cipher(SENTENCE, 36);
assertThat(cipheredSentence)
.isEqualTo(SENTENCE_SHIFTED_TEN);
}
@Test
void givenSentenceShiftedThreeAndShiftThree_whenDecipher_thenOriginalSentenceWithoutOverflow() {
String decipheredSentence = algorithm.decipher(SENTENCE_SHIFTED_THREE, 3);
assertThat(decipheredSentence)
.isEqualTo(SENTENCE);
}
@Test
void givenSentenceShiftedTenAndShiftTen_whenDecipher_thenOriginalSentenceWithOverflow() {
String decipheredSentence = algorithm.decipher(SENTENCE_SHIFTED_TEN, 10);
assertThat(decipheredSentence)
.isEqualTo(SENTENCE);
}
@Test
void givenSentenceShiftedTenAndShiftThirtySix_whenDecipher_thenOriginalSentenceWithOverflow() {
String decipheredSentence = algorithm.decipher(SENTENCE_SHIFTED_TEN, 36);
assertThat(decipheredSentence)
.isEqualTo(SENTENCE);
}
@Test
void givenSentenceShiftedThree_whenBreakCipher_thenOriginalSentence() {
int offset = algorithm.breakCipher(SENTENCE_SHIFTED_THREE);
assertThat(offset)
.isEqualTo(3);
assertThat(algorithm.decipher(SENTENCE_SHIFTED_THREE, offset))
.isEqualTo(SENTENCE);
}
@Test
void givenSentenceShiftedTen_whenBreakCipher_thenOriginalSentence() {
int offset = algorithm.breakCipher(SENTENCE_SHIFTED_TEN);
assertThat(offset)
.isEqualTo(10);
assertThat(algorithm.decipher(SENTENCE_SHIFTED_TEN, offset))
.isEqualTo(SENTENCE);
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/greedy/GreedyAlgorithmUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/greedy/GreedyAlgorithmUnitTest.java | package com.baeldung.algorithms.greedy;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertThrows;
import org.junit.jupiter.api.Test;
import java.util.Arrays;
class GreedyAlgorithmUnitTest {
private SocialConnector prepareNetwork() {
SocialConnector sc = new SocialConnector();
SocialUser root = new SocialUser("root");
SocialUser child1 = new SocialUser("child1");
SocialUser child2 = new SocialUser("child2");
SocialUser child3 = new SocialUser("child3");
SocialUser child21 = new SocialUser("child21");
SocialUser child211 = new SocialUser("child211");
SocialUser child2111 = new SocialUser("child2111");
SocialUser child31 = new SocialUser("child31");
SocialUser child311 = new SocialUser("child311");
SocialUser child3111 = new SocialUser("child3111");
child211.addFollowers(Arrays.asList(new SocialUser[]{child2111}));
child311.addFollowers(Arrays.asList(new SocialUser[]{child3111}));
child21.addFollowers(Arrays.asList(new SocialUser[]{child211}));
child31.addFollowers(Arrays.asList(new SocialUser[]{child311,
new SocialUser("child312"), new SocialUser("child313"), new SocialUser("child314")}));
child1.addFollowers(Arrays.asList(new SocialUser[]{new SocialUser("child11"), new SocialUser("child12")}));
child2.addFollowers(Arrays.asList(new SocialUser[]{child21, new SocialUser("child22"), new SocialUser("child23")}));
child3.addFollowers(Arrays.asList(new SocialUser[]{child31}));
root.addFollowers(Arrays.asList(new SocialUser[]{child1, child2, child3}));
sc.setUsers(Arrays.asList(new SocialUser[]{root, child1, child2, child3, child21, child31, child311, child211}));
return sc;
}
@Test
void greedyAlgorithmTest() {
GreedyAlgorithm ga = new GreedyAlgorithm(prepareNetwork());
assertEquals(ga.findMostFollowersPath("root"), 5);
}
@Test
void nongreedyAlgorithmTest() {
NonGreedyAlgorithm nga = new NonGreedyAlgorithm(prepareNetwork(), 0);
assertThrows(IllegalStateException.class, () -> {
nga.findMostFollowersPath("root");
});
}
@Test
void nongreedyAlgorithmUnboundedTest() {
SocialConnector sc = prepareNetwork();
sc.switchCounter();
NonGreedyAlgorithm nga = new NonGreedyAlgorithm(sc, 0);
assertEquals(nga.findMostFollowersPath("root"), 6);
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/topkelements/TopKElementsFinderUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/topkelements/TopKElementsFinderUnitTest.java | package com.baeldung.algorithms.topkelements;
import java.util.Arrays;
import java.util.List;
import static org.assertj.core.api.Java6Assertions.assertThat;
import org.junit.jupiter.api.Test;
class TopKElementsFinderUnitTest {
private final TopKElementsFinder<Integer> bruteForceFinder = new BruteForceTopKElementsFinder();
private final TopKElementsFinder<Integer> maxHeapFinder = new MaxHeapTopKElementsFinder();
private final TopKElementsFinder<Integer> treeSetFinder = new TreeSetTopKElementsFinder();
private final int k = 4;
private final List<Integer> distinctIntegers = Arrays.asList(1, 2, 3, 9, 7, 6, 12);
private final List<Integer> distinctIntegersTopK = Arrays.asList(9, 7, 6, 12);
private final List<Integer> nonDistinctIntegers = Arrays.asList(1, 2, 3, 3, 9, 9, 7, 6, 12);
private final List<Integer> nonDistinctIntegersTopK = Arrays.asList(9, 9, 7, 12);
@Test
void givenArrayDistinctIntegers_whenBruteForceFindTopK_thenReturnKLargest() {
assertThat(bruteForceFinder.findTopK(distinctIntegers, k)).containsOnlyElementsOf(distinctIntegersTopK);
}
@Test
void givenArrayDistinctIntegers_whenMaxHeapFindTopK_thenReturnKLargest() {
assertThat(maxHeapFinder.findTopK(distinctIntegers, k)).containsOnlyElementsOf(distinctIntegersTopK);
}
@Test
void givenArrayDistinctIntegers_whenTreeSetFindTopK_thenReturnKLargest() {
assertThat(treeSetFinder.findTopK(distinctIntegers, k)).containsOnlyElementsOf(distinctIntegersTopK);
}
@Test
void givenArrayNonDistinctIntegers_whenBruteForceFindTopK_thenReturnKLargest() {
assertThat(bruteForceFinder.findTopK(nonDistinctIntegers, k)).containsOnlyElementsOf(nonDistinctIntegersTopK);
}
@Test
void givenArrayNonDistinctIntegers_whenMaxHeapFindTopK_thenReturnKLargest() {
assertThat(maxHeapFinder.findTopK(nonDistinctIntegers, k)).containsOnlyElementsOf(nonDistinctIntegersTopK);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/gradientdescent/GradientDescentUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/gradientdescent/GradientDescentUnitTest.java | package com.baeldung.algorithms.gradientdescent;
import static org.junit.jupiter.api.Assertions.assertTrue;
import java.util.function.Function;
import org.junit.jupiter.api.Test;
class GradientDescentUnitTest {
@Test
void givenFunction_whenStartingPointIsOne_thenLocalMinimumIsFound() {
Function<Double, Double> df = x ->
StrictMath.abs(StrictMath.pow(x, 3)) - (3 * StrictMath.pow(x, 2)) + x;
GradientDescent gd = new GradientDescent();
double res = gd.findLocalMinimum(df, 1);
assertTrue(res > 1.78);
assertTrue(res < 1.84);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/balancedbrackets/BalancedBracketsUsingStringUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/balancedbrackets/BalancedBracketsUsingStringUnitTest.java | package com.baeldung.algorithms.balancedbrackets;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import static org.assertj.core.api.Assertions.assertThat;
class BalancedBracketsUsingStringUnitTest {
private BalancedBracketsUsingString balancedBracketsUsingString;
@BeforeEach
public void setup() {
balancedBracketsUsingString = new BalancedBracketsUsingString();
}
@Test
void givenNullInput_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingString.isBalanced(null);
assertThat(result).isFalse();
}
@Test
void givenEmptyString_whenCheckingForBalance_shouldReturnTrue() {
boolean result = balancedBracketsUsingString.isBalanced("");
assertThat(result).isTrue();
}
@Test
void givenInvalidCharacterString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingString.isBalanced("abc[](){}");
assertThat(result).isFalse();
}
@Test
void givenOddLengthString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingString.isBalanced("{{[]()}}}");
assertThat(result).isFalse();
}
@Test
void givenEvenLengthString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingString.isBalanced("{{[]()}}}}");
assertThat(result).isFalse();
}
@Test
void givenEvenLengthUnbalancedString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingString.isBalanced("{[(])}");
assertThat(result).isFalse();
}
@Test
void givenAnotherEvenLengthUnbalancedString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingString.isBalanced("{{}(");
assertThat(result).isFalse();
}
@Test
void givenEvenLengthBalancedString_whenCheckingForBalance_shouldReturnTrue() {
boolean result = balancedBracketsUsingString.isBalanced("{[()]}");
assertThat(result).isTrue();
}
@Test
void givenBalancedString_whenCheckingForBalance_shouldReturnTrue() {
boolean result = balancedBracketsUsingString.isBalanced("{{[[(())]]}}");
assertThat(result).isTrue();
}
@Test
void givenAnotherBalancedString_whenCheckingForBalance_shouldReturnTrue() {
boolean result = balancedBracketsUsingString.isBalanced("{{([])}}");
assertThat(result).isTrue();
}
@Test
void givenUnBalancedString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingString.isBalanced("{{)[](}}");
assertThat(result).isFalse();
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/balancedbrackets/BalancedBracketsUsingDequeUnitTest.java | algorithms-modules/algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/balancedbrackets/BalancedBracketsUsingDequeUnitTest.java | package com.baeldung.algorithms.balancedbrackets;
import static org.assertj.core.api.Assertions.assertThat;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
class BalancedBracketsUsingDequeUnitTest {
private BalancedBracketsUsingDeque balancedBracketsUsingDeque;
@BeforeEach
public void setup() {
balancedBracketsUsingDeque = new BalancedBracketsUsingDeque();
}
@Test
void givenNullInput_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingDeque.isBalanced(null);
assertThat(result).isFalse();
}
@Test
void givenEmptyString_whenCheckingForBalance_shouldReturnTrue() {
boolean result = balancedBracketsUsingDeque.isBalanced("");
assertThat(result).isTrue();
}
@Test
void givenInvalidCharacterString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingDeque.isBalanced("abc[](){}");
assertThat(result).isFalse();
}
@Test
void givenOddLengthString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingDeque.isBalanced("{{[]()}}}");
assertThat(result).isFalse();
}
@Test
void givenEvenLengthString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingDeque.isBalanced("{{[]()}}}}");
assertThat(result).isFalse();
}
@Test
void givenEvenLengthUnbalancedString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingDeque.isBalanced("{[(])}");
assertThat(result).isFalse();
}
@Test
void givenAnotherEvenLengthUnbalancedString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingDeque.isBalanced("{{}(");
assertThat(result).isFalse();
}
@Test
void givenEvenLengthBalancedString_whenCheckingForBalance_shouldReturnTrue() {
boolean result = balancedBracketsUsingDeque.isBalanced("{[()]}");
assertThat(result).isTrue();
}
@Test
void givenBalancedString_whenCheckingForBalance_shouldReturnTrue() {
boolean result = balancedBracketsUsingDeque.isBalanced("{{[[(())]]}}");
assertThat(result).isTrue();
}
@Test
void givenAnotherBalancedString_whenCheckingForBalance_shouldReturnTrue() {
boolean result = balancedBracketsUsingDeque.isBalanced("{{([])}}");
assertThat(result).isTrue();
}
@Test
void givenUnBalancedString_whenCheckingForBalance_shouldReturnFalse() {
boolean result = balancedBracketsUsingDeque.isBalanced("{{)[](}}");
assertThat(result).isFalse();
}
} | java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/kruskal/CycleDetector.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/kruskal/CycleDetector.java | package com.baeldung.algorithms.kruskal;
import java.util.ArrayList;
import java.util.List;
public class CycleDetector {
List<DisjointSetInfo> nodes;
public CycleDetector(int totalNodes) {
initDisjointSets(totalNodes);
}
public boolean detectCycle(Integer u, Integer v) {
Integer rootU = pathCompressionFind(u);
Integer rootV = pathCompressionFind(v);
if (rootU.equals(rootV)) {
return true;
}
unionByRank(rootU, rootV);
return false;
}
private void initDisjointSets(int totalNodes) {
nodes = new ArrayList<>(totalNodes);
for (int i = 0; i < totalNodes; i++) {
nodes.add(new DisjointSetInfo(i));
}
}
private Integer find(Integer node) {
Integer parent = nodes.get(node).getParentNode();
if (parent.equals(node)) {
return node;
} else {
return find(parent);
}
}
private Integer pathCompressionFind(Integer node) {
DisjointSetInfo setInfo = nodes.get(node);
Integer parent = setInfo.getParentNode();
if (parent.equals(node)) {
return node;
} else {
Integer parentNode = find(parent);
setInfo.setParentNode(parentNode);
return parentNode;
}
}
private void union(Integer rootU, Integer rootV) {
DisjointSetInfo setInfoU = nodes.get(rootU);
setInfoU.setParentNode(rootV);
}
private void unionByRank(int rootU, int rootV) {
DisjointSetInfo setInfoU = nodes.get(rootU);
DisjointSetInfo setInfoV = nodes.get(rootV);
int rankU = setInfoU.getRank();
int rankV = setInfoV.getRank();
if (rankU < rankV) {
setInfoU.setParentNode(rootV);
} else {
setInfoV.setParentNode(rootU);
if (rankU == rankV) {
setInfoU.setRank(rankU + 1);
}
}
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/kruskal/DisjointSetInfo.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/kruskal/DisjointSetInfo.java | package com.baeldung.algorithms.kruskal;
public class DisjointSetInfo {
private Integer parentNode;
private int rank;
DisjointSetInfo(Integer nodeNumber) {
setParentNode(nodeNumber);
setRank(1);
}
public Integer getParentNode() {
return parentNode;
}
public void setParentNode(Integer parentNode) {
this.parentNode = parentNode;
}
public int getRank() {
return rank;
}
public void setRank(int rank) {
this.rank = rank;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/kruskal/Kruskal.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/kruskal/Kruskal.java | package com.baeldung.algorithms.kruskal;
import com.google.common.graph.EndpointPair;
import com.google.common.graph.MutableValueGraph;
import com.google.common.graph.ValueGraph;
import com.google.common.graph.ValueGraphBuilder;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Set;
public class Kruskal {
public ValueGraph<Integer, Double> minSpanningTree(ValueGraph<Integer, Double> graph) {
return spanningTree(graph, true);
}
public ValueGraph<Integer, Double> maxSpanningTree(ValueGraph<Integer, Double> graph) {
return spanningTree(graph, false);
}
private ValueGraph<Integer, Double> spanningTree(ValueGraph<Integer, Double> graph, boolean minSpanningTree) {
Set<EndpointPair<Integer>> edges = graph.edges();
List<EndpointPair<Integer>> edgeList = new ArrayList<>(edges);
if (minSpanningTree) {
edgeList.sort(Comparator.comparing(e -> graph.edgeValue(e).get()));
} else {
edgeList.sort(Collections.reverseOrder(Comparator.comparing(e -> graph.edgeValue(e).get())));
}
int totalNodes = graph.nodes().size();
CycleDetector cycleDetector = new CycleDetector(totalNodes);
int edgeCount = 0;
MutableValueGraph<Integer, Double> spanningTree = ValueGraphBuilder.undirected().build();
for (EndpointPair<Integer> edge : edgeList) {
if (cycleDetector.detectCycle(edge.nodeU(), edge.nodeV())) {
continue;
}
spanningTree.putEdgeValue(edge.nodeU(), edge.nodeV(), graph.edgeValue(edge).get());
edgeCount++;
if (edgeCount == totalNodes - 1) {
break;
}
}
return spanningTree;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Board.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Board.java | package com.baeldung.algorithms.play2048;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class Board {
private static final Logger LOG = LoggerFactory.getLogger(Board.class);
private final int[][] board;
private final int score;
public Board(int size) {
assert(size > 0);
this.board = new int[size][];
this.score = 0;
for (int x = 0; x < size; ++x) {
this.board[x] = new int[size];
for (int y = 0; y < size; ++y) {
board[x][y] = 0;
}
}
}
private Board(int[][] board, int score) {
this.score = score;
this.board = new int[board.length][];
for (int x = 0; x < board.length; ++x) {
this.board[x] = Arrays.copyOf(board[x], board[x].length);
}
}
public int getSize() {
return board.length;
}
public int getScore() {
return score;
}
public int getCell(Cell cell) {
int x = cell.getX();
int y = cell.getY();
assert(x >= 0 && x < board.length);
assert(y >= 0 && y < board.length);
return board[x][y];
}
public boolean isEmpty(Cell cell) {
return getCell(cell) == 0;
}
public List<Cell> emptyCells() {
List<Cell> result = new ArrayList<>();
for (int x = 0; x < board.length; ++x) {
for (int y = 0; y < board[x].length; ++y) {
Cell cell = new Cell(x, y);
if (isEmpty(cell)) {
result.add(cell);
}
}
}
return result;
}
public Board placeTile(Cell cell, int number) {
if (!isEmpty(cell)) {
throw new IllegalArgumentException("That cell is not empty");
}
Board result = new Board(this.board, this.score);
result.board[cell.getX()][cell.getY()] = number;
return result;
}
public Board move(Move move) {
// Clone the board
int[][] tiles = new int[this.board.length][];
for (int x = 0; x < this.board.length; ++x) {
tiles[x] = Arrays.copyOf(this.board[x], this.board[x].length);
}
LOG.debug("Before move: {}", Arrays.deepToString(tiles));
// If we're doing an Left/Right move then transpose the board to make it a Up/Down move
if (move == Move.LEFT || move == Move.RIGHT) {
tiles = transpose(tiles);
LOG.debug("After transpose: {}", Arrays.deepToString(tiles));
}
// If we're doing a Right/Down move then reverse the board.
// With the above we're now always doing an Up move
if (move == Move.DOWN || move == Move.RIGHT) {
tiles = reverse(tiles);
LOG.debug("After reverse: {}", Arrays.deepToString(tiles));
}
LOG.debug("Ready to move: {}", Arrays.deepToString(tiles));
// Shift everything up
int[][] result = new int[tiles.length][];
int newScore = 0;
for (int x = 0; x < tiles.length; ++x) {
LinkedList<Integer> thisRow = new LinkedList<>();
for (int y = 0; y < tiles[0].length; ++y) {
if (tiles[x][y] > 0) {
thisRow.add(tiles[x][y]);
}
}
LOG.debug("Unmerged row: {}", thisRow);
LinkedList<Integer> newRow = new LinkedList<>();
while (thisRow.size() >= 2) {
int first = thisRow.pop();
int second = thisRow.peek();
LOG.debug("Looking at numbers {} and {}", first, second);
if (second == first) {
LOG.debug("Numbers match, combining");
int newNumber = first * 2;
newRow.add(newNumber);
newScore += newNumber;
thisRow.pop();
} else {
LOG.debug("Numbers don't match");
newRow.add(first);
}
}
newRow.addAll(thisRow);
LOG.debug("Merged row: {}", newRow);
result[x] = new int[tiles[0].length];
for (int y = 0; y < tiles[0].length; ++y) {
if (newRow.isEmpty()) {
result[x][y] = 0;
} else {
result[x][y] = newRow.pop();
}
}
}
LOG.debug("After moves: {}", Arrays.deepToString(result));
// Un-reverse the board
if (move == Move.DOWN || move == Move.RIGHT) {
result = reverse(result);
LOG.debug("After reverse: {}", Arrays.deepToString(result));
}
// Un-transpose the board
if (move == Move.LEFT || move == Move.RIGHT) {
result = transpose(result);
LOG.debug("After transpose: {}", Arrays.deepToString(result));
}
return new Board(result, this.score + newScore);
}
private static int[][] transpose(int[][] input) {
int[][] result = new int[input.length][];
for (int x = 0; x < input.length; ++x) {
result[x] = new int[input[0].length];
for (int y = 0; y < input[0].length; ++y) {
result[x][y] = input[y][x];
}
}
return result;
}
private static int[][] reverse(int[][] input) {
int[][] result = new int[input.length][];
for (int x = 0; x < input.length; ++x) {
result[x] = new int[input[0].length];
for (int y = 0; y < input[0].length; ++y) {
result[x][y] = input[x][input.length - y - 1];
}
}
return result;
}
@Override
public String toString() {
return Arrays.deepToString(board);
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
Board board1 = (Board) o;
return Arrays.deepEquals(board, board1.board);
}
@Override
public int hashCode() {
return Arrays.deepHashCode(board);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Move.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Move.java | package com.baeldung.algorithms.play2048;
public enum Move {
UP,
DOWN,
LEFT,
RIGHT
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Cell.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Cell.java | package com.baeldung.algorithms.play2048;
import java.util.StringJoiner;
public class Cell {
private int x;
private int y;
public Cell(int x, int y) {
this.x = x;
this.y = y;
}
public int getX() {
return x;
}
public int getY() {
return y;
}
@Override
public String toString() {
return new StringJoiner(", ", Cell.class.getSimpleName() + "[", "]").add("x=" + x).add("y=" + y).toString();
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Play2048.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Play2048.java | package com.baeldung.algorithms.play2048;
public class Play2048 {
private static final int SIZE = 4;
private static final int INITIAL_NUMBERS = 2;
public static void main(String[] args) {
// The board and players
Board board = new Board(SIZE);
Computer computer = new Computer();
Human human = new Human();
// The computer has two moves first
System.out.println("Setup");
System.out.println("=====");
for (int i = 0; i < INITIAL_NUMBERS; ++i) {
board = computer.makeMove(board);
}
printBoard(board);
do {
board = human.makeMove(board);
System.out.println("Human move");
System.out.println("==========");
printBoard(board);
board = computer.makeMove(board);
System.out.println("Computer move");
System.out.println("=============");
printBoard(board);
} while (!board.emptyCells().isEmpty());
System.out.println("Final Score: " + board.getScore());
}
private static void printBoard(Board board) {
StringBuilder topLines = new StringBuilder();
StringBuilder midLines = new StringBuilder();
for (int x = 0; x < board.getSize(); ++x) {
topLines.append("+--------");
midLines.append("| ");
}
topLines.append("+");
midLines.append("|");
for (int y = 0; y < board.getSize(); ++y) {
System.out.println(topLines);
System.out.println(midLines);
for (int x = 0; x < board.getSize(); ++x) {
Cell cell = new Cell(x, y);
System.out.print("|");
if (board.isEmpty(cell)) {
System.out.print(" ");
} else {
StringBuilder output = new StringBuilder(Integer.toString(board.getCell(cell)));
while (output.length() < 8) {
output.append(" ");
if (output.length() < 8) {
output.insert(0, " ");
}
}
System.out.print(output);
}
}
System.out.println("|");
System.out.println(midLines);
}
System.out.println(topLines);
System.out.println("Score: " + board.getScore());
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Human.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Human.java | package com.baeldung.algorithms.play2048;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import org.apache.commons.math3.util.Pair;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class Human {
private static final Logger LOG = LoggerFactory.getLogger(Human.class);
public Board makeMove(Board input) {
// For each move in MOVE
// Generate board from move
// Generate Score for Board
// Return board with the best score
//
// Generate Score
// If Depth Limit
// Return Final Score
// Total Score = 0
// For every empty square in new board
// Generate board with "2" in square
// Calculate Score
// Total Score += (Score * 0.9)
// Generate board with "4" in square
// Calculate Score
// Total Score += (Score * 0.1)
//
// Calculate Score
// For each move in MOVE
// Generate board from move
// Generate score for board
// Return the best generated score
return Arrays.stream(Move.values())
.parallel()
.map(input::move)
.filter(board -> !board.equals(input))
.max(Comparator.comparingInt(board -> generateScore(board, 0)))
.orElse(input);
}
private int generateScore(Board board, int depth) {
if (depth >= 3) {
int finalScore = calculateFinalScore(board);
LOG.debug("Final score for board {}: {}", board,finalScore);
return finalScore;
}
return board.emptyCells().stream()
.parallel()
.flatMap(cell -> Stream.of(new Pair<>(cell, 2), new Pair<>(cell, 4)))
.mapToInt(move -> {
LOG.debug("Simulating move {} at depth {}", move, depth);
Board newBoard = board.placeTile(move.getFirst(), move.getSecond());
int boardScore = calculateScore(newBoard, depth + 1);
int calculatedScore = (int) (boardScore * (move.getSecond() == 2 ? 0.9 : 0.1));
LOG.debug("Calculated score for board {} and move {} at depth {}: {}", newBoard, move, depth, calculatedScore);
return calculatedScore;
})
.sum();
}
private int calculateScore(Board board, int depth) {
return Arrays.stream(Move.values())
.parallel()
.map(board::move)
.filter(moved -> !moved.equals(board))
.mapToInt(newBoard -> generateScore(newBoard, depth))
.max()
.orElse(0);
}
private int calculateFinalScore(Board board) {
List<List<Integer>> rowsToScore = new ArrayList<>();
for (int i = 0; i < board.getSize(); ++i) {
List<Integer> row = new ArrayList<>();
List<Integer> col = new ArrayList<>();
for (int j = 0; j < board.getSize(); ++j) {
row.add(board.getCell(new Cell(i, j)));
col.add(board.getCell(new Cell(j, i)));
}
rowsToScore.add(row);
rowsToScore.add(col);
}
return rowsToScore.stream()
.parallel()
.mapToInt(row -> {
List<Integer> preMerged = row.stream()
.filter(value -> value != 0)
.collect(Collectors.toList());
int numMerges = 0;
int monotonicityLeft = 0;
int monotonicityRight = 0;
for (int i = 0; i < preMerged.size() - 1; ++i) {
Integer first = preMerged.get(i);
Integer second = preMerged.get(i + 1);
if (first.equals(second)) {
++numMerges;
} else if (first > second) {
monotonicityLeft += first - second;
} else {
monotonicityRight += second - first;
}
}
int score = 1000;
score += 250 * row.stream().filter(value -> value == 0).count();
score += 750 * numMerges;
score -= 10 * row.stream().mapToInt(value -> value).sum();
score -= 50 * Math.min(monotonicityLeft, monotonicityRight);
return score;
})
.sum();
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Computer.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/play2048/Computer.java | package com.baeldung.algorithms.play2048;
import java.security.SecureRandom;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class Computer {
private static final Logger LOG = LoggerFactory.getLogger(Computer.class);
private final SecureRandom rng = new SecureRandom();
public Board makeMove(Board input) {
List<Cell> emptyCells = input.emptyCells();
LOG.info("Number of empty cells: {}", emptyCells.size());
double numberToPlace = rng.nextDouble();
LOG.info("New number probability: {}", numberToPlace);
int indexToPlace = rng.nextInt(emptyCells.size());
Cell cellToPlace = emptyCells.get(indexToPlace);
LOG.info("Placing number into empty cell: {}", cellToPlace);
return input.placeTile(cellToPlace, numberToPlace >= 0.9 ? 4 : 2);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/boruvka/UnionFind.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/boruvka/UnionFind.java | package com.baeldung.algorithms.boruvka;
public class UnionFind {
private int[] parents;
private int[] ranks;
public UnionFind(int n) {
parents = new int[n];
ranks = new int[n];
for (int i = 0; i < n; i++) {
parents[i] = i;
ranks[i] = 0;
}
}
public int find(int u) {
while (u != parents[u]) {
u = parents[u];
}
return u;
}
public void union(int u, int v) {
int uParent = find(u);
int vParent = find(v);
if (uParent == vParent) {
return;
}
if (ranks[uParent] < ranks[vParent]) {
parents[uParent] = vParent;
} else if (ranks[uParent] > ranks[vParent]) {
parents[vParent] = uParent;
} else {
parents[vParent] = uParent;
ranks[uParent]++;
}
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/boruvka/BoruvkaMST.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/boruvka/BoruvkaMST.java | package com.baeldung.algorithms.boruvka;
import com.google.common.graph.EndpointPair;
import com.google.common.graph.MutableValueGraph;
import com.google.common.graph.ValueGraphBuilder;
public class BoruvkaMST {
private static MutableValueGraph<Integer, Integer> mst = ValueGraphBuilder.undirected()
.build();
private static int totalWeight;
public BoruvkaMST(MutableValueGraph<Integer, Integer> graph) {
int size = graph.nodes().size();
UnionFind uf = new UnionFind(size);
// repeat at most log N times or until we have N-1 edges
for (int t = 1; t < size && mst.edges().size() < size - 1; t = t + t) {
EndpointPair<Integer>[] closestEdgeArray = new EndpointPair[size];
// foreach tree in graph, find closest edge
for (EndpointPair<Integer> edge : graph.edges()) {
int u = edge.nodeU();
int v = edge.nodeV();
int uParent = uf.find(u);
int vParent = uf.find(v);
if (uParent == vParent) {
continue; // same tree
}
int weight = graph.edgeValueOrDefault(u, v, 0);
if (closestEdgeArray[uParent] == null) {
closestEdgeArray[uParent] = edge;
}
if (closestEdgeArray[vParent] == null) {
closestEdgeArray[vParent] = edge;
}
int uParentWeight = graph.edgeValueOrDefault(closestEdgeArray[uParent].nodeU(), closestEdgeArray[uParent].nodeV(), 0);
int vParentWeight = graph.edgeValueOrDefault(closestEdgeArray[vParent].nodeU(), closestEdgeArray[vParent].nodeV(), 0);
if (weight < uParentWeight) {
closestEdgeArray[uParent] = edge;
}
if (weight < vParentWeight) {
closestEdgeArray[vParent] = edge;
}
}
// add newly discovered edges to MST
for (int i = 0; i < size; i++) {
EndpointPair<Integer> edge = closestEdgeArray[i];
if (edge != null) {
int u = edge.nodeU();
int v = edge.nodeV();
int weight = graph.edgeValueOrDefault(u, v, 0);
// don't add the same edge twice
if (uf.find(u) != uf.find(v)) {
mst.putEdgeValue(u, v, weight);
totalWeight += weight;
uf.union(u, v);
}
}
}
}
}
public MutableValueGraph<Integer, Integer> getMST() {
return mst;
}
public int getTotalWeight() {
return totalWeight;
}
public String toString() {
return "MST: " + mst.toString() + " | Total Weight: " + totalWeight;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/linkedlist/LinkedListReversal.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/linkedlist/LinkedListReversal.java | package com.baeldung.algorithms.linkedlist;
public class LinkedListReversal {
ListNode reverseList(ListNode head) {
ListNode previous = null;
ListNode current = head;
while (current != null) {
ListNode nextElement = current.getNext();
current.setNext(previous);
previous = current;
current = nextElement;
}
return previous;
}
ListNode reverseListRecursive(ListNode head) {
if (head == null) {
return null;
}
if (head.getNext() == null) {
return head;
}
ListNode node = reverseListRecursive(head.getNext());
head.getNext().setNext(head);
head.setNext(null);
return node;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/linkedlist/ListNode.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/linkedlist/ListNode.java | package com.baeldung.algorithms.linkedlist;
public class ListNode {
private int data;
private ListNode next;
ListNode(int data) {
this.data = data;
this.next = null;
}
public int getData() {
return data;
}
public ListNode getNext() {
return next;
}
public void setData(int data) {
this.data = data;
}
public void setNext(ListNode next) {
this.next = next;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/minheapmerge/MinHeap.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/minheapmerge/MinHeap.java | package com.baeldung.algorithms.minheapmerge;
public class MinHeap {
HeapNode[] heapNodes;
public MinHeap(HeapNode heapNodes[]) {
this.heapNodes = heapNodes;
heapifyFromLastLeafsParent();
}
void heapifyFromLastLeafsParent() {
int lastLeafsParentIndex = getParentNodeIndex(heapNodes.length);
while (lastLeafsParentIndex >= 0) {
heapify(lastLeafsParentIndex);
lastLeafsParentIndex--;
}
}
void heapify(int index) {
int leftNodeIndex = getLeftNodeIndex(index);
int rightNodeIndex = getRightNodeIndex(index);
int smallestElementIndex = index;
if (leftNodeIndex < heapNodes.length && heapNodes[leftNodeIndex].element < heapNodes[index].element) {
smallestElementIndex = leftNodeIndex;
}
if (rightNodeIndex < heapNodes.length && heapNodes[rightNodeIndex].element < heapNodes[smallestElementIndex].element) {
smallestElementIndex = rightNodeIndex;
}
if (smallestElementIndex != index) {
swap(index, smallestElementIndex);
heapify(smallestElementIndex);
}
}
int getParentNodeIndex(int index) {
return (index - 1) / 2;
}
int getLeftNodeIndex(int index) {
return (2 * index + 1);
}
int getRightNodeIndex(int index) {
return (2 * index + 2);
}
HeapNode getRootNode() {
return heapNodes[0];
}
void heapifyFromRoot() {
heapify(0);
}
void swap(int i, int j) {
HeapNode temp = heapNodes[i];
heapNodes[i] = heapNodes[j];
heapNodes[j] = temp;
}
static int[] merge(int[][] array) {
HeapNode[] heapNodes = new HeapNode[array.length];
int resultingArraySize = 0;
for (int i = 0; i < array.length; i++) {
HeapNode node = new HeapNode(array[i][0], i);
heapNodes[i] = node;
resultingArraySize += array[i].length;
}
MinHeap minHeap = new MinHeap(heapNodes);
int[] resultingArray = new int[resultingArraySize];
for (int i = 0; i < resultingArraySize; i++) {
HeapNode root = minHeap.getRootNode();
resultingArray[i] = root.element;
if (root.nextElementIndex < array[root.arrayIndex].length) {
root.element = array[root.arrayIndex][root.nextElementIndex++];
} else {
root.element = Integer.MAX_VALUE;
}
minHeap.heapifyFromRoot();
}
return resultingArray;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/minheapmerge/HeapNode.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/minheapmerge/HeapNode.java | package com.baeldung.algorithms.minheapmerge;
public class HeapNode {
int element;
int arrayIndex;
int nextElementIndex = 1;
public HeapNode(int element, int arrayIndex) {
this.element = element;
this.arrayIndex = arrayIndex;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/caesarcipher/CaesarCipher.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/caesarcipher/CaesarCipher.java | package com.baeldung.algorithms.caesarcipher;
import org.apache.commons.math3.stat.inference.ChiSquareTest;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Arrays;
import java.util.stream.IntStream;
public class CaesarCipher {
private final Logger log = LoggerFactory.getLogger(CaesarCipher.class);
private static final char LETTER_A = 'a';
private static final char LETTER_Z = 'z';
private static final int ALPHABET_SIZE = LETTER_Z - LETTER_A + 1;
private static final double[] ENGLISH_LETTERS_PROBABILITIES = {0.073, 0.009, 0.030, 0.044, 0.130, 0.028, 0.016, 0.035, 0.074, 0.002, 0.003, 0.035, 0.025, 0.078, 0.074, 0.027, 0.003, 0.077, 0.063, 0.093, 0.027, 0.013, 0.016, 0.005, 0.019, 0.001};
public String cipher(String message, int offset) {
StringBuilder result = new StringBuilder();
for (char character : message.toCharArray()) {
if (character != ' ') {
int originalAlphabetPosition = character - LETTER_A;
int newAlphabetPosition = (originalAlphabetPosition + offset) % ALPHABET_SIZE;
char newCharacter = (char) (LETTER_A + newAlphabetPosition);
result.append(newCharacter);
} else {
result.append(character);
}
}
return result.toString();
}
public String decipher(String message, int offset) {
return cipher(message, ALPHABET_SIZE - (offset % ALPHABET_SIZE));
}
public int breakCipher(String message) {
return probableOffset(chiSquares(message));
}
private double[] chiSquares(String message) {
double[] expectedLettersFrequencies = expectedLettersFrequencies(message.length());
double[] chiSquares = new double[ALPHABET_SIZE];
for (int offset = 0; offset < chiSquares.length; offset++) {
String decipheredMessage = decipher(message, offset);
long[] lettersFrequencies = observedLettersFrequencies(decipheredMessage);
double chiSquare = new ChiSquareTest().chiSquare(expectedLettersFrequencies, lettersFrequencies);
chiSquares[offset] = chiSquare;
}
return chiSquares;
}
private long[] observedLettersFrequencies(String message) {
return IntStream.rangeClosed(LETTER_A, LETTER_Z)
.mapToLong(letter -> countLetter((char) letter, message))
.toArray();
}
private long countLetter(char letter, String message) {
return message.chars()
.filter(character -> character == letter)
.count();
}
private double[] expectedLettersFrequencies(int messageLength) {
return Arrays.stream(ENGLISH_LETTERS_PROBABILITIES)
.map(probability -> probability * messageLength)
.toArray();
}
private int probableOffset(double[] chiSquares) {
int probableOffset = 0;
for (int offset = 0; offset < chiSquares.length; offset++) {
log.debug(String.format("Chi-Square for offset %d: %.2f", offset, chiSquares[offset]));
if (chiSquares[offset] < chiSquares[probableOffset]) {
probableOffset = offset;
}
}
return probableOffset;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/NonGreedyAlgorithm.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/NonGreedyAlgorithm.java | package com.baeldung.algorithms.greedy;
import java.util.List;
public class NonGreedyAlgorithm {
int currentLevel = 0;
final int maxLevel = 3;
SocialConnector tc;
public NonGreedyAlgorithm(SocialConnector tc, int level) {
super();
this.tc = tc;
this.currentLevel = level;
}
public long findMostFollowersPath(String account) {
List<SocialUser> followers = tc.getFollowers(account);
long total = currentLevel > 0 ? followers.size() : 0;
if (currentLevel < maxLevel ) {
currentLevel++;
long[] count = new long[followers.size()];
int i = 0;
for (SocialUser el : followers) {
NonGreedyAlgorithm sub = new NonGreedyAlgorithm(tc, currentLevel);
count[i] = sub.findMostFollowersPath(el.getUsername());
i++;
}
long max = 0;
for (; i > 0; i--) {
if (count[i-1] > max )
max = count[i-1];
}
return total + max;
}
return total;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/SocialConnector.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/SocialConnector.java | package com.baeldung.algorithms.greedy;
import java.util.ArrayList;
import java.util.List;
import lombok.Getter;
import lombok.Setter;
public class SocialConnector {
private boolean isCounterEnabled = true;
private int counter = 4;
@Getter @Setter List<SocialUser> users;
public SocialConnector() {
users = new ArrayList<>();
}
public boolean switchCounter() {
this.isCounterEnabled = !this.isCounterEnabled;
return this.isCounterEnabled;
}
public List<SocialUser> getFollowers(String account) {
if (counter < 0)
throw new IllegalStateException ("API limit reached");
else {
if(this.isCounterEnabled) counter--;
for(SocialUser user : users) {
if (user.getUsername().equals(account)) {
return user.getFollowers();
}
}
}
return new ArrayList<>();
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/FollowersPath.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/FollowersPath.java | package com.baeldung.algorithms.greedy;
import java.util.ArrayList;
import java.util.List;
public class FollowersPath {
private List<Follower> accounts;
private long count;
public FollowersPath() {
super();
this.accounts = new ArrayList<>();
}
public List<Follower> getAccounts() {
return accounts;
}
public long getCount() {
return count;
}
public void addFollower(String username, long count) {
accounts.add(new Follower(username, count));
}
public void addCount(long count) {
this.count += count;
}
@Override
public String toString() {
String details = "";
for(Follower a : accounts) {
details+=a.toString() + ", ";
}
return "Total: " + count + ", \n\r" +
" Details: { " + "\n\r" +
details + "\n\r" +
" }";
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/SocialUser.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/SocialUser.java | package com.baeldung.algorithms.greedy;
import java.util.ArrayList;
import java.util.List;
import lombok.Getter;
public class SocialUser {
@Getter private String username;
@Getter private List<SocialUser> followers;
public SocialUser(String username) {
super();
this.username = username;
this.followers = new ArrayList<>();
}
public SocialUser(String username, List<SocialUser> followers) {
super();
this.username = username;
this.followers = followers;
}
public long getFollowersCount() {
return followers.size();
}
public void addFollowers(List<SocialUser> followers) {
this.followers.addAll(followers);
}
@Override
public boolean equals(Object obj) {
return ((SocialUser) obj).getUsername().equals(username);
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/Follower.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/Follower.java | package com.baeldung.algorithms.greedy;
import lombok.Getter;
public class Follower {
@Getter String username;
@Getter long count;
public Follower(String username, long count) {
super();
this.username = username;
this.count = count;
}
@Override
public String toString() {
return "User: " + username + ", Followers: " + count + "\n\r" ;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/GreedyAlgorithm.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/greedy/GreedyAlgorithm.java | package com.baeldung.algorithms.greedy;
import java.util.List;
public class GreedyAlgorithm {
int currentLevel = 0;
final int maxLevel = 3;
SocialConnector sc;
FollowersPath fp;
public GreedyAlgorithm(SocialConnector sc) {
super();
this.sc = sc;
this.fp = new FollowersPath();
}
public long findMostFollowersPath(String account) {
long max = 0;
SocialUser toFollow = null;
List<SocialUser> followers = sc.getFollowers(account);
for (SocialUser el : followers) {
long followersCount = el.getFollowersCount();
if (followersCount > max) {
toFollow = el;
max = followersCount;
}
}
if (currentLevel < maxLevel - 1) {
currentLevel++;
max += findMostFollowersPath(toFollow.getUsername());
return max;
} else {
return max;
}
}
public FollowersPath getFollowers() {
return fp;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/topkelements/TreeSetTopKElementsFinder.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/topkelements/TreeSetTopKElementsFinder.java | package com.baeldung.algorithms.topkelements;
import java.util.Comparator;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;
import java.util.stream.Collectors;
public class TreeSetTopKElementsFinder implements TopKElementsFinder<Integer> {
public List<Integer> findTopK(List<Integer> input, int k) {
Set<Integer> sortedSet = new TreeSet<>(Comparator.reverseOrder());
sortedSet.addAll(input);
return sortedSet.stream().limit(k).collect(Collectors.toList());
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/topkelements/TopKElementsFinder.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/topkelements/TopKElementsFinder.java | package com.baeldung.algorithms.topkelements;
import java.util.List;
public interface TopKElementsFinder<T extends Comparable<T>> {
List<T> findTopK(List<T> input, int k);
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/topkelements/BruteForceTopKElementsFinder.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/topkelements/BruteForceTopKElementsFinder.java | package com.baeldung.algorithms.topkelements;
import java.util.ArrayList;
import java.util.List;
public class BruteForceTopKElementsFinder implements TopKElementsFinder<Integer> {
public List<Integer> findTopK(List<Integer> input, int k) {
List<Integer> array = new ArrayList<>(input);
List<Integer> topKList = new ArrayList<>();
for (int i = 0; i < k; i++) {
int maxIndex = 0;
for (int j = 1; j < array.size(); j++) {
if (array.get(j) > array.get(maxIndex)) {
maxIndex = j;
}
}
topKList.add(array.remove(maxIndex));
}
return topKList;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/topkelements/MaxHeapTopKElementsFinder.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/topkelements/MaxHeapTopKElementsFinder.java | package com.baeldung.algorithms.topkelements;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.PriorityQueue;
public class MaxHeapTopKElementsFinder implements TopKElementsFinder<Integer> {
public List<Integer> findTopK(List<Integer> input, int k) {
PriorityQueue<Integer> maxHeap = new PriorityQueue<>();
input.forEach(number -> {
maxHeap.add(number);
if (maxHeap.size() > k) {
maxHeap.poll();
}
});
List<Integer> topKList = new ArrayList<>(maxHeap);
Collections.reverse(topKList);
return topKList;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
eugenp/tutorials | https://github.com/eugenp/tutorials/blob/4463e58ffb73fe599bac2479abd84598c6e70a1a/algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/gradientdescent/GradientDescent.java | algorithms-modules/algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/gradientdescent/GradientDescent.java | package com.baeldung.algorithms.gradientdescent;
import java.util.function.Function;
public class GradientDescent {
private final double precision = 0.000001;
public double findLocalMinimum(Function<Double, Double> f, double initialX) {
double stepCoefficient = 0.1;
double previousStep = 1.0;
double currentX = initialX;
double previousX = initialX;
double previousY = f.apply(previousX);
int iter = 100;
currentX += stepCoefficient * previousY;
while (previousStep > precision && iter > 0) {
iter--;
double currentY = f.apply(currentX);
if (currentY > previousY) {
stepCoefficient = -stepCoefficient / 2;
}
previousX = currentX;
currentX += stepCoefficient * previousY;
previousY = currentY;
previousStep = StrictMath.abs(currentX - previousX);
}
return currentX;
}
}
| java | MIT | 4463e58ffb73fe599bac2479abd84598c6e70a1a | 2026-01-04T14:45:57.069771Z | false |
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