[leetcode-404-Sum of Left Leaves]

Posted hellowOOOrld

tags:

篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了[leetcode-404-Sum of Left Leaves]相关的知识,希望对你有一定的参考价值。

Find the sum of all left leaves in a given binary tree.

Example:

    3
   /   9  20
    /     15   7

There are two left leaves in the binary tree, with values 9 and 15 respectively. Return 24.
思路:
递归遍历,判断是左叶子加入sum.
 void tr(TreeNode* root, int& sum)
     {
         if (root == NULL)return;
         if (root->left != NULL && root->left->left == NULL && root->left->right == NULL)sum += root->left->val;
         tr(root->left, sum);
         tr(root->right, sum);
     }
     int sumOfLeftLeaves(TreeNode* root)
     {
         if (root == NULL)return 0;
         int sum = 0;
         tr(root, sum);
         return sum;
     }

 



以上是关于[leetcode-404-Sum of Left Leaves]的主要内容,如果未能解决你的问题,请参考以下文章

#Leetcode# 404. Sum of Left Leaves

leetcode-404. Sum of Left Leaves

[leetcode-404-Sum of Left Leaves]

LeetCode 404. Sum of Left Leaves

LeetCode - 404. Sum of Left Leaves

leetcode 404 Sum of Left Leaves