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] ]
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/** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { private: vector<vector<int> > paths; public: void dfs(TreeNode *node,int sum,int csum,vector<int> onePath){ //a能为引用 if(node==NULL) return; if(node->left==NULL && node->right==NULL){ if(node->val+csum==sum){ onePath.push_back(node->val); paths.push_back(onePath); } return; } onePath.push_back(node->val); dfs(node->left,sum,csum+node->val,onePath); dfs(node->right,sum,csum+node->val,onePath); } vector<vector<int> > pathSum(TreeNode *root, int sum) { paths.clear(); vector<int> onePath; dfs(root,sum,0,onePath); return paths; } };
时间: 2024-10-29 04:29:27