Merge pull request neetcode-gh#100 from berkslv/main

Added Javascript solutions for 9, 110 and 704.

Author: neetcode-gh

javascript/110-Balanced-Binary-Tree.js

@@ -0,0 +1,26 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {boolean}
+ */
+ var isBalanced = function (root) {
+    if (!root) return true
+    const left = findHeight(root.left)
+    const right = findHeight(root.right)
+    return Math.abs(left - right) <= 1 && isBalanced(root.left) && isBalanced(root.right)
+};
+
+function findHeight(node) {
+    if (node == null) return 0;
+    return 1 + Math.max(this.findHeight(node.left), this.findHeight(node.right));
+}
+
+// Runtime: 78 ms, faster than 90.43% of JavaScript online submissions for Balanced Binary Tree.
+// Memory Usage: 47.1 MB, less than 32.41% of JavaScript online submissions for Balanced Binary Tree.

javascript/704-Binary-Search.js

@@ -0,0 +1,27 @@
+/**
+ * @param {number[]} nums
+ * @param {number} target
+ * @return {number}
+ */
+var search = function (nums, target) {
+
+    let left = 0;
+    let right = nums.length - 1;
+
+    while (left <= right) {
+        let middle = Math.floor((left + right) / 2);
+
+        if (nums[middle] === target) {
+            return middle;
+        } else if (nums[middle] < target) {
+            left = middle + 1;
+        } else {
+            right = middle - 1;
+        }
+    }
+
+    return -1;
+};
+
+// Runtime: 98 ms, faster than 34.02% of JavaScript online submissions for Binary Search.
+// Memory Usage: 44.3 MB, less than 99.18% of JavaScript online submissions for Binary Search.

javascript/9-Palindrome-Number.js

@@ -0,0 +1,24 @@
+/**
+ * @param {number} x
+ * @return {boolean}
+ */
+var isPalindrome = function (x) {
+
+    // Creates array from int characters
+    // 121 -> [1,2,1]
+    let arr = Array.from(String(x), Number);
+
+    // Uses two pointer
+    for (let i = 0; i < arr.length; i++) {
+        if (arr[i] !== arr[arr.length - 1 - i]) {
+            return false;
+        }
+    }
+
+    return true;
+};
+
+
+// Runtime: 302 ms, faster than 40.50% of JavaScript online submissions for Palindrome Number.
+// Memory Usage: 51.8 MB, less than 8.36% of JavaScript online submissions for Palindrome Number.
+