Add solution #662

Author: JoshCrozier

0662-maximum-width-of-binary-tree.js

@@ -0,0 +1,52 @@
+/**
+ * 662. Maximum Width of Binary Tree
+ * https://leetcode.com/problems/maximum-width-of-binary-tree/
+ * Difficulty: Medium
+ *
+ * Given the root of a binary tree, return the maximum width of the given tree.
+ *
+ * The maximum width of a tree is the maximum width among all levels.
+ *
+ * The width of one level is defined as the length between the end-nodes (the leftmost and
+ * rightmost non-null nodes), where the null nodes between the end-nodes that would be present
+ * in a complete binary tree extending down to that level are also counted into the length
+ * calculation.
+ *
+ * It is guaranteed that the answer will in the range of a 32-bit signed integer.
+ */
+
+/**
+ * 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 {number}
+ */
+var widthOfBinaryTree = function(root) {
+  const queue = [[root, 0n]];
+  let result = 0n;
+
+  while (queue.length) {
+    const total = queue.length;
+    const levelStart = queue[0][1];
+    let levelEnd;
+
+    for (let i = 0; i < total; i++) {
+      const [node, index] = queue.shift();
+      levelEnd = index;
+      if (node.left) queue.push([node.left, index * 2n]);
+      if (node.right) queue.push([node.right, index * 2n + 1n]);
+    }
+
+    result = result > (levelEnd - levelStart + 1n)
+      ? result
+      : (levelEnd - levelStart + 1n);
+  }
+
+  return Number(result);
+};

README.md

@@ -498,6 +498,7 @@
 658|[Find K Closest Elements](./0658-find-k-closest-elements.js)|Medium|
 659|[Split Array into Consecutive Subsequences](./0659-split-array-into-consecutive-subsequences.js)|Medium|
 661|[Image Smoother](./0661-image-smoother.js)|Easy|
+662|[Maximum Width of Binary Tree](./0662-maximum-width-of-binary-tree.js)|Medium|
 680|[Valid Palindrome II](./0680-valid-palindrome-ii.js)|Easy|
 684|[Redundant Connection](./0684-redundant-connection.js)|Medium|
 686|[Repeated String Match](./0686-repeated-string-match.js)|Easy|