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Path Sum II深度优先找路径

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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 Tree Depth-first Search
 
/** * 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;    }};

 

Path Sum II深度优先找路径