题目描述：

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

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

return

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

代码：

void search_path(TreeNode * node,int sum,vector<int> temp,vector<vector<int> > &result)
{
    if(node == NULL)
        return;
    temp.push_back(node->val);
    if(node->left == NULL && node->right == NULL)
    {
        int current_sum = 0;
        for(int i = 0;i < temp.size();i++)
            current_sum = current_sum + temp[i];
        if(sum == current_sum)
            result.push_back(temp);
        return;
    }
    if(node->left != NULL)
        search_path(node->left,sum,temp,result);
    if(node->right != NULL)
        search_path(node->right,sum,temp,result);
}

vector<vector<int> > pathSum(TreeNode *root, int sum)
{
    vector<vector<int> > result;
    TreeNode * node = root;
    vector<int> temp;
    search_path(node,sum,temp,result);
    return result;
}

LeetCode:Path Sum II