Merge branch 'master' into refactor/SubsetSum

Author: alxkm

pmd-exclude.properties

@@ -12,7 +12,7 @@ com.thealgorithms.datastructures.crdt.LWWElementSet=UselessParentheses
 com.thealgorithms.datastructures.crdt.Pair=UnusedPrivateField
 com.thealgorithms.datastructures.graphs.AStar=UselessParentheses
 com.thealgorithms.datastructures.graphs.AdjacencyMatrixGraph=CollapsibleIfStatements,UnnecessaryFullyQualifiedName,UselessParentheses
-com.thealgorithms.datastructures.graphs.BipartiteGrapfDFS=CollapsibleIfStatements
+com.thealgorithms.datastructures.graphs.BipartiteGraphDFS=CollapsibleIfStatements
 com.thealgorithms.datastructures.graphs.Kruskal=UselessParentheses
 com.thealgorithms.datastructures.hashmap.hashing.HashMapCuckooHashing=UselessParentheses
 com.thealgorithms.datastructures.heaps.FibonacciHeap=UselessParentheses

pom.xml

@@ -50,7 +50,7 @@
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-lang3</artifactId>
-            <version>3.16.0</version>
+            <version>3.17.0</version>
         </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>

src/main/java/com/thealgorithms/datastructures/graphs/BipartiteGrapfDFS.java renamed to src/main/java/com/thealgorithms/datastructures/graphs/BipartiteGraphDFS.java

@@ -14,8 +14,8 @@
  *
  * Output : YES
  */
-public final class BipartiteGrapfDFS {
-    private BipartiteGrapfDFS() {
+public final class BipartiteGraphDFS {
+    private BipartiteGraphDFS() {
     }
 
     private static boolean bipartite(int v, ArrayList<ArrayList<Integer>> adj, int[] color, int node) {

src/main/java/com/thealgorithms/datastructures/lists/MergeKSortedLinkedlist.java renamed to src/main/java/com/thealgorithms/datastructures/lists/MergeKSortedLinkedList.java

@@ -7,7 +7,7 @@
 /**
  * @author Arun Pandey (https://github.com/pandeyarun709)
  */
-public class MergeKSortedLinkedlist {
+public class MergeKSortedLinkedList {
 
     /**
      * This function merge K sorted LinkedList

src/main/java/com/thealgorithms/maths/LeastCommonMultiple.java

@@ -1,41 +1,27 @@
 package com.thealgorithms.maths;
 
-import java.util.Scanner;
-
 /**
  * Is a common mathematics concept to find the smallest value number
  * that can be divide using either number without having the remainder.
  * https://maticschool.blogspot.com/2013/11/find-least-common-multiple-lcm.html
  * @author LauKinHoong
  */
-
 public final class LeastCommonMultiple {
     private LeastCommonMultiple() {
     }
 
     /**
-     * Driver Code
-     */
-    public static void main(String[] args) {
-        Scanner input = new Scanner(System.in);
-        System.out.println("Please enter first number >> ");
-        int num1 = input.nextInt();
-        System.out.println("Please enter second number >> ");
-        int num2 = input.nextInt();
-        System.out.println("The least common multiple of two numbers is >> " + lcm(num1, num2));
-        input.close();
-    }
-
-    /*
-     * get least common multiple from two number
+     * Finds the least common multiple of two numbers.
+     *
+     * @param num1 The first number.
+     * @param num2 The second number.
+     * @return The least common multiple of num1 and num2.
      */
     public static int lcm(int num1, int num2) {
         int high;
         int num3;
         int cmv = 0;
-        /*
-         * value selection for the numerator
-         */
+
         if (num1 > num2) {
             high = num1;
             num3 = num1;

src/main/java/com/thealgorithms/stacks/LargestRectangle.java

@@ -11,7 +11,7 @@ public final class LargestRectangle {
     private LargestRectangle() {
     }
 
-    public static String largestRectanglehistogram(int[] heights) {
+    public static String largestRectangleHistogram(int[] heights) {
         int n = heights.length;
         int maxArea = 0;
         Stack<int[]> st = new Stack<>();
@@ -32,7 +32,7 @@ public static String largestRectanglehistogram(int[] heights) {
     }
 
     public static void main(String[] args) {
-        assert largestRectanglehistogram(new int[] {2, 1, 5, 6, 2, 3}).equals("10");
-        assert largestRectanglehistogram(new int[] {2, 4}).equals("4");
+        assert largestRectangleHistogram(new int[] {2, 1, 5, 6, 2, 3}).equals("10");
+        assert largestRectangleHistogram(new int[] {2, 4}).equals("4");
     }
 }

src/main/java/com/thealgorithms/strings/ReverseWordsInString.java

@@ -13,7 +13,6 @@ private ReverseWordsInString() {
      * @param s the input string
      * @return A string created by reversing the order of the words in {@code s}
      */
-
     public static String reverseWordsInString(final String s) {
         var words = s.trim().split("\\s+");
         Collections.reverse(Arrays.asList(words));

src/main/java/com/thealgorithms/strings/Upper.java

@@ -15,13 +15,13 @@ public static void main(String[] args) {
     }
 
     /**
-     * Converts all of the characters in this {@code String} to upper case
+     * Converts all the characters in this {@code String} to upper case
      *
      * @param s the string to convert
      * @return the {@code String}, converted to uppercase.
      */
     public static String toUpperCase(String s) {
-        if (s == null || "".equals(s)) {
+        if (s == null || s.isEmpty()) {
             return s;
         }
         char[] values = s.toCharArray();

src/main/java/com/thealgorithms/strings/WordLadder.java

@@ -4,58 +4,28 @@
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Queue;
+import java.util.Set;
 
-/*
-    **Problem Statement:**
-    A transformation sequence from word beginWord to word endWord using a dictionary wordList is a
-   sequence of words beginWord -> s1 -> s2 -> ... -> sk such that:
-
-    Every adjacent pair of words differs by a single letter.
-    Every si for 1 <= i <= k is in wordList. Note that beginWord does not need to be in wordList.
-    sk == endWord
-    Given two words, beginWord and endWord, and a dictionary wordList, return the number of words in
-   the shortest transformation sequence from beginWord to endWord, or 0 if no such sequence exists.
-
-    **Example 1:**
-    Input: beginWord = "hit", endWord = "cog", wordList = ["hot","dot","dog","lot","log","cog"]
-    Output: 5
-    Explanation: One shortest transformation sequence is "hit" -> "hot" -> "dot" -> "dog" -> cog",
-   which is 5 words long.
-
-    **Example 2:**
-    Input: beginWord = "hit", endWord = "cog", wordList = ["hot","dot","dog","lot","log"]
-    Output: 0
-    Explanation: The endWord "cog" is not in wordList, therefore there is no valid transformation
-   sequence.
-
-    **Constraints:**
-    1 <= beginWord.length <= 10
-    endWord.length == beginWord.length
-    1 <= wordList.length <= 5000
-    wordList[i].length == beginWord.length
-    beginWord, endWord, and wordList[i] consist of lowercase English letters.
-    beginWord != endWord
-    All the words in wordList are unique.
+/**
+ * Class to find the shortest transformation sequence from a beginWord to an endWord using a dictionary of words.
+ * A transformation sequence is a sequence of words where each adjacent pair differs by exactly one letter.
  */
-
-final class WordLadder {
+public final class WordLadder {
     private WordLadder() {
     }
 
     /**
-     * This function finds the ladderLength
+     * Finds the shortest transformation sequence from beginWord to endWord.
      *
-     * @param beginWord: Starting word of the ladder
-     * @param endWord: Ending word of the ladder
-     * @param wordList: This list contains the words which needs to be included
-     * in ladder.
-     * @return ladderLength: This function will return the ladderLength(level)
-     * if the endword is there. Otherwise, will return the length as 0.
+     * @param beginWord the starting word of the transformation sequence
+     * @param endWord the target word of the transformation sequence
+     * @param wordList a list of words that can be used in the transformation sequence
+     * @return the number of words in the shortest transformation sequence, or 0 if no such sequence exists
      */
     public static int ladderLength(String beginWord, String endWord, List<String> wordList) {
-        HashSet<String> set = new HashSet<>(wordList);
+        Set<String> wordSet = new HashSet<>(wordList);
 
-        if (!set.contains(endWord)) {
+        if (!wordSet.contains(endWord)) {
             return 0;
         }
 
@@ -66,25 +36,25 @@ public static int ladderLength(String beginWord, String endWord, List<String> wo
         while (!queue.isEmpty()) {
             int size = queue.size();
             for (int i = 0; i < size; i++) {
-                String curr = queue.poll();
-                char[] wordsChars = curr.toCharArray();
-                for (int j = 0; j < wordsChars.length; j++) {
-                    char originalChars = wordsChars[j];
+                String currentWord = queue.poll();
+                char[] currentWordChars = currentWord.toCharArray();
+                for (int j = 0; j < currentWordChars.length; j++) {
+                    char originalChar = currentWordChars[j];
                     for (char c = 'a'; c <= 'z'; c++) {
-                        if (wordsChars[j] == c) {
+                        if (currentWordChars[j] == c) {
                             continue;
                         }
-                        wordsChars[j] = c;
-                        String transformedWord = String.valueOf(wordsChars);
-                        if (transformedWord.equals(endWord)) {
+                        currentWordChars[j] = c;
+                        String newWord = new String(currentWordChars);
+
+                        if (newWord.equals(endWord)) {
                             return level + 1;
                         }
-                        if (set.contains(transformedWord)) {
-                            set.remove(transformedWord);
-                            queue.offer(transformedWord);
+                        if (wordSet.remove(newWord)) {
+                            queue.offer(newWord);
                         }
                     }
-                    wordsChars[j] = originalChars;
+                    currentWordChars[j] = originalChar;
                 }
             }
             level++;

src/test/java/com/thealgorithms/maths/LeastCommonMultipleTest.java

@@ -1,27 +1,21 @@
 package com.thealgorithms.maths;
 
-import org.junit.jupiter.api.Assertions;
-import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
-public class LeastCommonMultipleTest {
+import java.util.stream.Stream;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
 
-    /*
-     * Test for first number greater than second number
-     */
-    @Test
-    public void testForFirst() {
-        int result = LeastCommonMultiple.lcm(6, 8);
-        int expected = 24;
-        Assertions.assertEquals(result, expected);
+class LeastCommonMultipleTest {
+
+    @ParameterizedTest
+    @MethodSource("provideTestCases")
+    void testLcm(int num1, int num2, int expected) {
+        assertEquals(expected, LeastCommonMultiple.lcm(num1, num2));
     }
 
-    /*
-     * Test for second number greater than first number
-     */
-    @Test
-    public void testForSecond() {
-        int result = LeastCommonMultiple.lcm(8, 6);
-        int expected = 24;
-        Assertions.assertEquals(result, expected);
+    private static Stream<Arguments> provideTestCases() {
+        return Stream.of(Arguments.of(12, 18, 36), Arguments.of(5, 10, 10), Arguments.of(7, 3, 21), Arguments.of(21, 6, 42), Arguments.of(1, 1, 1), Arguments.of(8, 12, 24), Arguments.of(14, 35, 70), Arguments.of(15, 25, 75), Arguments.of(100, 25, 100), Arguments.of(0, 10, 0));
     }
 }

src/test/java/com/thealgorithms/stacks/LargestRectangleTest.java

@@ -11,19 +11,19 @@ void testLargestRectangleHistogramWithTypicalCases() {
         // Typical case with mixed heights
         int[] heights = {2, 1, 5, 6, 2, 3};
         String expected = "10";
-        String result = LargestRectangle.largestRectanglehistogram(heights);
+        String result = LargestRectangle.largestRectangleHistogram(heights);
         assertEquals(expected, result);
 
         // Another typical case with increasing heights
         heights = new int[] {2, 4};
         expected = "4";
-        result = LargestRectangle.largestRectanglehistogram(heights);
+        result = LargestRectangle.largestRectangleHistogram(heights);
         assertEquals(expected, result);
 
         // Case with multiple bars of the same height
         heights = new int[] {4, 4, 4, 4};
         expected = "16";
-        result = LargestRectangle.largestRectanglehistogram(heights);
+        result = LargestRectangle.largestRectangleHistogram(heights);
         assertEquals(expected, result);
     }
 
@@ -32,19 +32,19 @@ void testLargestRectangleHistogramWithEdgeCases() {
         // Edge case with an empty array
         int[] heights = {};
         String expected = "0";
-        String result = LargestRectangle.largestRectanglehistogram(heights);
+        String result = LargestRectangle.largestRectangleHistogram(heights);
         assertEquals(expected, result);
 
         // Edge case with a single bar
         heights = new int[] {5};
         expected = "5";
-        result = LargestRectangle.largestRectanglehistogram(heights);
+        result = LargestRectangle.largestRectangleHistogram(heights);
         assertEquals(expected, result);
 
         // Edge case with all bars of height 0
         heights = new int[] {0, 0, 0};
         expected = "0";
-        result = LargestRectangle.largestRectanglehistogram(heights);
+        result = LargestRectangle.largestRectangleHistogram(heights);
         assertEquals(expected, result);
     }
 
@@ -56,7 +56,7 @@ void testLargestRectangleHistogramWithLargeInput() {
             heights[i] = 1;
         }
         String expected = "10000";
-        String result = LargestRectangle.largestRectanglehistogram(heights);
+        String result = LargestRectangle.largestRectangleHistogram(heights);
         assertEquals(expected, result);
     }
 
@@ -65,13 +65,13 @@ void testLargestRectangleHistogramWithComplexCases() {
         // Complex case with a mix of heights
         int[] heights = {6, 2, 5, 4, 5, 1, 6};
         String expected = "12";
-        String result = LargestRectangle.largestRectanglehistogram(heights);
+        String result = LargestRectangle.largestRectangleHistogram(heights);
         assertEquals(expected, result);
 
         // Case with a peak in the middle
         heights = new int[] {2, 1, 5, 6, 2, 3, 1};
         expected = "10";
-        result = LargestRectangle.largestRectanglehistogram(heights);
+        result = LargestRectangle.largestRectangleHistogram(heights);
         assertEquals(expected, result);
     }
 }

src/test/java/com/thealgorithms/strings/WordLadderTest.java

@@ -5,6 +5,8 @@
 import java.util.Arrays;
 import java.util.List;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
 
 public class WordLadderTest {
 
@@ -38,4 +40,12 @@ public void testWordLadder2() {
         List<String> wordList2 = Arrays.asList("hot", "dot", "dog", "lot", "log");
         assertEquals(WordLadder.ladderLength("hit", "cog", wordList2), 0);
     }
+
+    @ParameterizedTest
+    @CsvSource({"'a', 'c', 'b,c', 2", "'a', 'c', 'a', 0", "'a', 'a', 'a', 0", "'ab', 'cd', 'ad,bd,cd', 3", "'a', 'd', 'b,c,d', 2", "'a', 'd', 'b,c,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,d', 2"})
+    void testLadderLength(String beginWord, String endWord, String wordListStr, int expectedLength) {
+        List<String> wordList = List.of(wordListStr.split(","));
+        int result = WordLadder.ladderLength(beginWord, endWord, wordList);
+        assertEquals(expectedLength, result);
+    }
 }