Path Sum II

Path Sum IIOct 14 '123844 / 10801

Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum.

For example:
Given the below binary tree and sum = 22,

              5             / \            4   8           /   / \          11  13  4         /  \    / \        7    2  5   1

return

[   [5,4,11,2],   [5,8,4,5]]

添加記錄數組

 

/** * Definition for binary tree * struct TreeNode { *     int val; *     TreeNode *left; *     TreeNode *right; *     TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */class Solution {    int targetSum;    int depthSum;    vector<vector<int> > res;    vector<int> cur;    void depthSearch(TreeNode* root)    {        if(root)        {            if(root->left == NULL && root->right == NULL)            {                if(root->val + depthSum == targetSum)                {                    cur.push_back(root->val);                    res.push_back(cur);                    cur.pop_back();                }                return;            }            depthSum += root->val;            cur.push_back(root->val);            depthSearch(root->left);            depthSearch(root->right);            depthSum -= root->val;            cur.pop_back();        }    }public:    vector<vector<int> > pathSum(TreeNode *root, int sum) {        // Start typing your C/C++ solution below        // DO NOT write int main() function        res.clear();        cur.clear();        depthSum = 0;        targetSum = sum;        depthSearch(root);        return res;    }};