113. 路径总和 II 

 1 /**
 2  * Definition for a binary tree node.
 3  * struct TreeNode {
 4  *     int val;
 5  *     TreeNode *left;
 6  *     TreeNode *right;
 7  *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 8  * };
 9  */
10 class Solution 
11 {
12     vector<vector<int>> ans;
13     vector<int> out; 
14 public:
15     vector<vector<int>> pathSum(TreeNode* root, int sum) 
16     {
17         int target = 0;
18         solve(root,sum,target);
19         return ans;
20     }
21 
22     void solve(TreeNode* root, int sum,int target)
23     {
24         if(!root) return;
25         out.push_back(root->val);
26         target += root->val;
27 
28         if(root->left == NULL && root->right == NULL && target == sum)
29         {
30             ans.push_back(out);
31             out.pop_back();
32             return;
33         }
34         solve(root->left,sum,target);
35         solve(root->right,sum,target);
36 
37         out.pop_back();
38         target -= root->val;
39     }
40 };

 

posted @ 2020-04-01 15:42  Jinxiaobo0509  阅读(103)  评论(0)    收藏  举报