diff --git a/javascript/2331-evaluate-boolean-binary-tree.js b/javascript/2331-evaluate-boolean-binary-tree.js new file mode 100644 index 000000000..8f9018b57 --- /dev/null +++ b/javascript/2331-evaluate-boolean-binary-tree.js @@ -0,0 +1,31 @@ +/** + * 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) + * } + */ +/** + * DFS | Tree-traversal + * Time O(n) | Space O(1) + * https://leetcode.com/problems/evaluate-boolean-binary-tree + * @param {TreeNode} root + * @return {boolean} + */ +var evaluateTree = function(root) { + return dfs(root); +}; + +const dfs = (node) => { + + if (!node.left && !node.right && node.val) return true; + if (!node.left && !node.right && !node.val) return false; + + const is2 = (node.val === 2); + if (is2) return dfs(node.left) || dfs(node.right); + + const is3 = (node.val === 3); + if (is3) return dfs(node.left) && dfs(node.right); + +}