Create 0116-populating-next-right-pointers-in-each-node.js

Solved populating-next-right-pointers-in-each-node in JS.

Author: aadil42

javascript/0116-populating-next-right-pointers-in-each-node.js

@@ -0,0 +1,37 @@
+/**
+ * BFS
+ * Time O(n) | Space O(1)
+ * 
+ * https://leetcode.com/problems/populating-next-right-pointers-in-each-node/
+ * // Definition for a Node.
+ * function Node(val, left, right, next) {
+ *    this.val = val === undefined ? null : val;
+ *    this.left = left === undefined ? null : left;
+ *    this.right = right === undefined ? null : right;
+ *    this.next = next === undefined ? null : next;
+ * };
+ */
+/**
+ * @param {Node} root
+ * @return {Node}
+ */
+
+var connect = function(root) {
+
+    let currentNode = root;
+    let nextLevelNode = root && root.left;
+
+    while(currentNode && nextLevelNode) {
+        currentNode.left.next = currentNode.right;
+        if(currentNode.next) {
+            currentNode.right.next = currentNode.next.left;
+        }
+        currentNode = currentNode.next;
+        if(!currentNode) {
+            currentNode = nextLevelNode;
+            nextLevelNode = currentNode.left;
+        }
+    }
+
+    return root;
+};