#Leetcode# 515. Find Largest Value in Each Tree Row
https://leetcode.com/problems/find-largest-value-in-each-tree-row/
You need to find the largest value in each row of a binary tree.
Example:
Input: 1 / \ 3 2 / \ \ 5 3 9 Output: [1, 3, 9]
代码:
/** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: vector<int> largestValues(TreeNode* root) { vector<int> ans; if(!root) return ans; helper(root, ans, 1); return ans; } void helper(TreeNode* root, vector<int>& ans, int depth) { if(depth > ans.size()) ans.push_back(root -> val); else ans[depth - 1] = max(ans[depth - 1], root -> val); if(root -> left) helper(root -> left, ans, depth + 1); if(root -> right) helper(root -> right, ans, depth + 1); } };
今天是不吃宵夜的第二天!!!今天也是被二叉树折磨得死去活来的一天