style: enable MethodName in CheckStyle

checkstyle.xml

@@ -112,7 +112,7 @@
     <module name="LocalFinalVariableName"/>
     <!-- TODO <module name="LocalVariableName"/> -->
     <!-- TODO <module name="MemberName"/> -->
-    <!-- TODO <module name="MethodName"/> -->
+    <module name="MethodName"/>
     <module name="PackageName"/>
     <!-- TODO <module name="ParameterName"/> -->
     <module name="StaticVariableName"/>

src/main/java/com/thealgorithms/backtracking/PowerSum.java

@@ -12,12 +12,12 @@ public class PowerSum {
     private int sum = 0;
 
     public int powSum(int N, int X) {
-        Sum(N, X, 1);
+        sum(N, X, 1);
         return count;
     }
 
     // here i is the natural number which will be raised by X and added in sum.
-    public void Sum(int N, int X, int i) {
+    public void sum(int N, int X, int i) {
         // if sum is equal to N that is one of our answer and count is increased.
         if (sum == N) {
             count++;
@@ -26,15 +26,15 @@ public void Sum(int N, int X, int i) {
           // result is less than N.
         else if (sum + power(i, X) <= N) {
             sum += power(i, X);
-            Sum(N, X, i + 1);
+            sum(N, X, i + 1);
             // backtracking and removing the number added last since no possible combination is
             // there with it.
             sum -= power(i, X);
         }
         if (power(i, X) < N) {
             // calling the sum function with next natural number after backtracking if when it is
             // raised to X is still less than X.
-            Sum(N, X, i + 1);
+            sum(N, X, i + 1);
         }
     }
 

src/main/java/com/thealgorithms/ciphers/DES.java

@@ -106,7 +106,7 @@ private String[] getSubkeys(String originalKey) {
         return subKeys;
     }
 
-    private String XOR(String a, String b) {
+    private String xOR(String a, String b) {
         int i;
         int l = a.length();
         StringBuilder xor = new StringBuilder();
@@ -143,7 +143,7 @@ private String feistel(String messageBlock, String key) {
         for (i = 0; i < 48; i++) {
             expandedKey.append(messageBlock.charAt(EXPANSION[i] - 1));
         }
-        String mixedKey = XOR(expandedKey.toString(), key);
+        String mixedKey = xOR(expandedKey.toString(), key);
         StringBuilder substitutedString = new StringBuilder();
 
         // Let us now use the s-boxes to transform each 6 bit (length here) block to 4 bits
@@ -175,7 +175,7 @@ private String encryptBlock(String message, String[] keys) {
         // Iterate 16 times
         for (i = 0; i < 16; i++) {
             String Ln = R0; // Previous Right block
-            String Rn = XOR(L0, feistel(R0, keys[i]));
+            String Rn = xOR(L0, feistel(R0, keys[i]));
             L0 = Ln;
             R0 = Rn;
         }

src/main/java/com/thealgorithms/datastructures/heaps/LeftistHeap.java

@@ -91,7 +91,7 @@ public void insert(int a) {
     }
 
     // Returns and removes the minimum element in the heap
-    public int extract_min() {
+    public int extractMin() {
         // If is empty return -1
         if (isEmpty()) return -1;
 
@@ -101,17 +101,17 @@ public int extract_min() {
     }
 
     // Function returning a list of an in order traversal of the data structure
-    public ArrayList<Integer> in_order() {
+    public ArrayList<Integer> inOrder() {
         ArrayList<Integer> lst = new ArrayList<>();
-        in_order_aux(root, lst);
+        inOrderAux(root, lst);
         return new ArrayList<>(lst);
     }
 
     // Auxiliary function for in_order
-    private void in_order_aux(Node n, ArrayList<Integer> lst) {
+    private void inOrderAux(Node n, ArrayList<Integer> lst) {
         if (n == null) return;
-        in_order_aux(n.left, lst);
+        inOrderAux(n.left, lst);
         lst.add(n.element);
-        in_order_aux(n.right, lst);
+        inOrderAux(n.right, lst);
     }
 }

src/main/java/com/thealgorithms/datastructures/trees/GenericTree.java

@@ -25,10 +25,10 @@ private static final class Node {
     private final Node root;
     public GenericTree() { // Constructor
         Scanner scn = new Scanner(System.in);
-        root = create_treeG(null, 0, scn);
+        root = createTreeG(null, 0, scn);
     }
 
-    private Node create_treeG(Node node, int childIndex, Scanner scanner) {
+    private Node createTreeG(Node node, int childIndex, Scanner scanner) {
         // display
         if (node == null) {
             System.out.println("Enter root's data");
@@ -41,7 +41,7 @@ private Node create_treeG(Node node, int childIndex, Scanner scanner) {
         System.out.println("number of children");
         int number = scanner.nextInt();
         for (int i = 0; i < number; i++) {
-            Node child = create_treeG(node, i, scanner);
+            Node child = createTreeG(node, i, scanner);
             node.child.add(child);
         }
         return node;
@@ -51,17 +51,17 @@ private Node create_treeG(Node node, int childIndex, Scanner scanner) {
      * Function to display the generic tree
      */
     public void display() { // Helper function
-        display_1(root);
+        display1(root);
     }
 
-    private void display_1(Node parent) {
+    private void display1(Node parent) {
         System.out.print(parent.data + "=>");
         for (int i = 0; i < parent.child.size(); i++) {
             System.out.print(parent.child.get(i).data + " ");
         }
         System.out.println(".");
         for (int i = 0; i < parent.child.size(); i++) {
-            display_1(parent.child.get(i));
+            display1(parent.child.get(i));
         }
     }
 

src/main/java/com/thealgorithms/datastructures/trees/nearestRightKey.java

@@ -8,7 +8,7 @@ private NearestRightKey() {
     }
 
     public static void main(String[] args) {
-        NRKTree root = BuildTree();
+        NRKTree root = buildTree();
         Scanner sc = new Scanner(System.in);
         System.out.print("Enter first number: ");
         int inputX0 = sc.nextInt();
@@ -17,7 +17,7 @@ public static void main(String[] args) {
         sc.close();
     }
 
-    public static NRKTree BuildTree() {
+    public static NRKTree buildTree() {
         int randomX = ThreadLocalRandom.current().nextInt(0, 100 + 1);
         NRKTree root = new NRKTree(null, null, randomX);
 

src/main/java/com/thealgorithms/dynamicprogramming/KadaneAlgorithm.java

@@ -10,7 +10,7 @@ public final class KadaneAlgorithm {
     private KadaneAlgorithm() {
     }
 
-    public static boolean max_Sum(int[] a, int predicted_answer) {
+    public static boolean maxSum(int[] a, int predicted_answer) {
         int sum = a[0];
         int running_sum = 0;
         for (int k : a) {

src/main/java/com/thealgorithms/dynamicprogramming/LongestAlternatingSubsequence.java

@@ -16,7 +16,7 @@ private LongestAlternatingSubsequence() {
     }
 
     /* Function to return longest alternating subsequence length*/
-    static int AlternatingLength(int[] arr, int n) {
+    static int alternatingLength(int[] arr, int n) {
         /*
 
                 las[i][0] = Length of the longest
@@ -68,6 +68,6 @@ public static void main(String[] args) {
         int[] arr = {10, 22, 9, 33, 49, 50, 31, 60};
         int n = arr.length;
         System.out.println("Length of Longest "
-            + "alternating subsequence is " + AlternatingLength(arr, n));
+            + "alternating subsequence is " + alternatingLength(arr, n));
     }
 }

src/main/java/com/thealgorithms/dynamicprogramming/LongestIncreasingSubsequence.java

@@ -20,7 +20,7 @@ private static int upperBound(int[] ar, int l, int r, int key) {
         return r;
     }
 
-    public static int LIS(int[] array) {
+    public static int lis(int[] array) {
         int N = array.length;
         if (N == 0) {
             return 0;

src/main/java/com/thealgorithms/dynamicprogramming/LongestPalindromicSubsequence.java

@@ -12,14 +12,14 @@ public static void main(String[] args) {
         String a = "BBABCBCAB";
         String b = "BABCBAB";
 
-        String aLPS = LPS(a);
-        String bLPS = LPS(b);
+        String aLPS = lps(a);
+        String bLPS = lps(b);
 
         System.out.println(a + " => " + aLPS);
         System.out.println(b + " => " + bLPS);
     }
 
-    public static String LPS(String original) throws IllegalArgumentException {
+    public static String lps(String original) throws IllegalArgumentException {
         StringBuilder reverse = new StringBuilder(original);
         reverse = reverse.reverse();
         return recursiveLPS(original, reverse.toString());

src/main/java/com/thealgorithms/dynamicprogramming/LongestPalindromicSubstring.java

@@ -11,14 +11,14 @@ public static void main(String[] args) {
         String a = "babad";
         String b = "cbbd";
 
-        String aLPS = LPS(a);
-        String bLPS = LPS(b);
+        String aLPS = lps(a);
+        String bLPS = lps(b);
 
         System.out.println(a + " => " + aLPS);
         System.out.println(b + " => " + bLPS);
     }
 
-    private static String LPS(String input) {
+    private static String lps(String input) {
         if (input == null || input.length() == 0) {
             return input;
         }

src/main/java/com/thealgorithms/dynamicprogramming/MatrixChainRecursiveTopDownMemoisation.java

@@ -10,18 +10,18 @@ public final class MatrixChainRecursiveTopDownMemoisation {
     private MatrixChainRecursiveTopDownMemoisation() {
     }
 
-    static int Memoized_Matrix_Chain(int[] p) {
+    static int memoizedMatrixChain(int[] p) {
         int n = p.length;
         int[][] m = new int[n][n];
         for (int i = 0; i < n; i++) {
             for (int j = 0; j < n; j++) {
                 m[i][j] = Integer.MAX_VALUE;
             }
         }
-        return Lookup_Chain(m, p, 1, n - 1);
+        return lookupChain(m, p, 1, n - 1);
     }
 
-    static int Lookup_Chain(int[][] m, int[] p, int i, int j) {
+    static int lookupChain(int[][] m, int[] p, int i, int j) {
         if (i == j) {
             m[i][j] = 0;
             return m[i][j];
@@ -30,7 +30,7 @@ static int Lookup_Chain(int[][] m, int[] p, int i, int j) {
             return m[i][j];
         } else {
             for (int k = i; k < j; k++) {
-                int q = Lookup_Chain(m, p, i, k) + Lookup_Chain(m, p, k + 1, j) + (p[i - 1] * p[k] * p[j]);
+                int q = lookupChain(m, p, i, k) + lookupChain(m, p, k + 1, j) + (p[i - 1] * p[k] * p[j]);
                 if (q < m[i][j]) {
                     m[i][j] = q;
                 }
@@ -43,6 +43,6 @@ static int Lookup_Chain(int[][] m, int[] p, int i, int j) {
     // respectively output should be  Minimum number of multiplications is 38
     public static void main(String[] args) {
         int[] arr = {1, 2, 3, 4, 5};
-        System.out.println("Minimum number of multiplications is " + Memoized_Matrix_Chain(arr));
+        System.out.println("Minimum number of multiplications is " + memoizedMatrixChain(arr));
     }
 }

src/main/java/com/thealgorithms/dynamicprogramming/WineProblem.java

@@ -16,22 +16,22 @@ private WineProblem() {
 
     // Method 1: Using Recursion
     // Time Complexity=0(2^N) Space Complexity=Recursion extra space
-    public static int WPRecursion(int[] arr, int si, int ei) {
+    public static int wpRecursion(int[] arr, int si, int ei) {
         int n = arr.length;
         int year = (n - (ei - si + 1)) + 1;
         if (si == ei) {
             return arr[si] * year;
         }
 
-        int start = WPRecursion(arr, si + 1, ei) + arr[si] * year;
-        int end = WPRecursion(arr, si, ei - 1) + arr[ei] * year;
+        int start = wpRecursion(arr, si + 1, ei) + arr[si] * year;
+        int end = wpRecursion(arr, si, ei - 1) + arr[ei] * year;
 
         return Math.max(start, end);
     }
 
     // Method 2: Top-Down DP(Memoization)
     // Time Complexity=0(N*N) Space Complexity=0(N*N)+Recursion extra space
-    public static int WPTD(int[] arr, int si, int ei, int[][] strg) {
+    public static int wptd(int[] arr, int si, int ei, int[][] strg) {
         int n = arr.length;
         int year = (n - (ei - si + 1)) + 1;
         if (si == ei) {
@@ -41,8 +41,8 @@ public static int WPTD(int[] arr, int si, int ei, int[][] strg) {
         if (strg[si][ei] != 0) {
             return strg[si][ei];
         }
-        int start = WPTD(arr, si + 1, ei, strg) + arr[si] * year;
-        int end = WPTD(arr, si, ei - 1, strg) + arr[ei] * year;
+        int start = wptd(arr, si + 1, ei, strg) + arr[si] * year;
+        int end = wptd(arr, si, ei - 1, strg) + arr[ei] * year;
 
         int ans = Math.max(start, end);
 
@@ -53,7 +53,7 @@ public static int WPTD(int[] arr, int si, int ei, int[][] strg) {
 
     // Method 3: Bottom-Up DP(Tabulation)
     // Time Complexity=0(N*N/2)->0(N*N) Space Complexity=0(N*N)
-    public static int WPBU(int[] arr) {
+    public static int wpbu(int[] arr) {
         int n = arr.length;
         int[][] strg = new int[n][n];
 
@@ -76,9 +76,9 @@ public static int WPBU(int[] arr) {
 
     public static void main(String[] args) {
         int[] arr = {2, 3, 5, 1, 4};
-        System.out.println("Method 1: " + WPRecursion(arr, 0, arr.length - 1));
-        System.out.println("Method 2: " + WPTD(arr, 0, arr.length - 1, new int[arr.length][arr.length]));
-        System.out.println("Method 3: " + WPBU(arr));
+        System.out.println("Method 1: " + wpRecursion(arr, 0, arr.length - 1));
+        System.out.println("Method 2: " + wptd(arr, 0, arr.length - 1, new int[arr.length][arr.length]));
+        System.out.println("Method 3: " + wpbu(arr));
     }
 }
 // Memoization vs Tabulation : https://www.geeksforgeeks.org/tabulation-vs-memoization/

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

@@ -10,7 +10,7 @@ private SquareRootWithBabylonianMethod() {
      * @param num contains elements
      * @return the square root of num
      */
-    public static float square_Root(float num) {
+    public static float squareRoot(float num) {
         float a = num;
         float b = 1;
         double e = 0.000001;

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

@@ -11,7 +11,7 @@ public final class TrinomialTriangle {
     private TrinomialTriangle() {
     }
 
-    public static int TrinomialValue(int n, int k) {
+    public static int trinomialValue(int n, int k) {
         if (n == 0 && k == 0) {
             return 1;
         }
@@ -20,17 +20,17 @@ public static int TrinomialValue(int n, int k) {
             return 0;
         }
 
-        return (TrinomialValue(n - 1, k - 1) + TrinomialValue(n - 1, k) + TrinomialValue(n - 1, k + 1));
+        return (trinomialValue(n - 1, k - 1) + trinomialValue(n - 1, k) + trinomialValue(n - 1, k + 1));
     }
 
     public static void printTrinomial(int n) {
         for (int i = 0; i < n; i++) {
             for (int j = -i; j <= 0; j++) {
-                System.out.print(TrinomialValue(i, j) + " ");
+                System.out.print(trinomialValue(i, j) + " ");
             }
 
             for (int j = 1; j <= i; j++) {
-                System.out.print(TrinomialValue(i, j) + " ");
+                System.out.print(trinomialValue(i, j) + " ");
             }
 
             System.out.println();