style: enable MultipleVariableDeclarations in checkstyle (#5175)

Co-authored-by: vaibhav <vaibhav.waghmare@techprescient.com>

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

@@ -9,7 +9,9 @@ public class AVLTree {
         private int key;
         private int balance;
         private int height;
-        private Node left, right, parent;
+        private Node left;
+        private Node right;
+        private Node parent;
 
         Node(int k, Node p) {
             key = k;

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

@@ -14,14 +14,16 @@ public final class LCA {
         ArrayList<ArrayList<Integer>> adj = new ArrayList<>();
 
         // v is the number of vertices and e is the number of edges
-        int v = SCANNER.nextInt(), e = v - 1;
+        int v = SCANNER.nextInt();
+        int e = v - 1;
 
         for (int i = 0; i < v; i++) {
             adj.add(new ArrayList<Integer>());
         }
 
         // Storing the given tree as an adjacency list
-        int to, from;
+        int to;
+        int from;
         for (int i = 0; i < e; i++) {
             to = SCANNER.nextInt();
             from = SCANNER.nextInt();
@@ -40,7 +42,8 @@ public final class LCA {
         dfs(adj, 0, -1, parent, depth);
 
         // Inputting the two vertices whose LCA is to be calculated
-        int v1 = SCANNER.nextInt(), v2 = SCANNER.nextInt();
+        int v1 = SCANNER.nextInt();
+        int v2 = SCANNER.nextInt();
 
         // Outputting the LCA
         System.out.println(getLCA(v1, v2, depth, parent));

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

@@ -10,10 +10,12 @@ public class LazySegmentTree {
      */
     static class Node {
 
-        private final int start, end; // start and end of the segment represented by this node
+        private final int start;
+        private final int end; // start and end of the segment represented by this node
         private int value; // value is the sum of all elements in the range [start, end)
         private int lazy; // lazied value that should be added to children nodes
-        Node left, right; // left and right children
+        Node left;
+        Node right; // left and right children
 
         Node(int start, int end, int value) {
             this.start = start;

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

@@ -10,7 +10,8 @@ class TreeNode {
     // Members
 
     int key;
-    TreeNode left, right;
+    TreeNode left;
+    TreeNode right;
 
     // Constructor
     TreeNode(int key) {

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

@@ -12,8 +12,11 @@ public class RedBlackBST {
 
     private class Node {
 
-        int key = -1, color = B;
-        Node left = nil, right = nil, p = nil;
+        int key = -1;
+        int color = B;
+        Node left = nil;
+        Node right = nil;
+        Node p = nil;
 
         Node(int key) {
             this.key = key;

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

@@ -29,7 +29,8 @@ public class TreeRandomNode {
     private final class Node {
 
         int item;
-        Node left, right;
+        Node left;
+        Node right;
     }
 
     // Using an arraylist to store the inorder traversal of the given binary tree

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

@@ -47,7 +47,8 @@ public final class VerticalOrderTraversal {
 
         /* min and max stores leftmost and right most index to
                  later print the tree in vertical fashion.*/
-        int max = 0, min = 0;
+        int max = 0;
+        int min = 0;
         queue.offer(root);
         index.offer(0);