LeetCode Path Sum II

Path Sum II

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]]

Solution:

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