javascript iterate through a binary tree
/** * 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 sum = 0; var traverse = function(item, isLeft){ item.left && traverse(item.left, true); if (isLeft && item.left == null && item.right == null){ sum += item.val; } item.right && traverse(item.right, false); } var sumOfLeftLeaves = function(root) { sum = 0; if (root === null){ return 0; } traverse(root, false); return sum; };
