// Source : https://oj.leetcode.com/problems/path-sum-ii/
// Author : Hao Chen
// Date : 2014-07-01
/**********************************************************************************
*
* 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]
* ]
*
*
**********************************************************************************/
/**
* 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 > pathSum(TreeNode *root, int sum) {
vector > result;
vector v;
generatePathSum(root, sum, v, result);
return result;
}
void generatePathSum(TreeNode *root, int sum, vector v, vector >& result) {
if (root==NULL) {
return;
}
if (root->left==NULL && root->right==NULL) {
if (root->val == sum){
v.push_back(root->val);
result.push_back(v);
}
return;
}
v.push_back(root->val);
if (root->left) {
generatePathSum(root->left, sum - root->val, v, result);
}
if (root->right) {
generatePathSum(root->right, sum - root->val, v, result);
}
}
};