23.二叉树中和为某一值的路径

// 24.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <vector>
using namespace::std;

struct TreeNode {
int val;
struct TreeNode *left;
struct TreeNode *right;
TreeNode(int x) :
val(x), left(NULL), right(NULL) {
}
};
class Solution {
public:
	vector<vector<int> > FindPath(TreeNode* root, int exp) {
		vector<vector<int>> retVec;
		if (root == NULL)return retVec;
		vector<int> path;
		int cur = 0;
		recursive(root, retVec, path, exp, cur);
		return retVec;
	}

	void recursive(TreeNode* root, vector<vector<int>>& retVec, vector<int>& path, int sum, int& cur) {
		path.push_back(root->val);
		cur = cur + root->val;
		bool isLeaf = (root->left == NULL) && (root->right == NULL);
		if (isLeaf && sum == cur) {
			retVec.push_back(path);
		}

		if (root->left != NULL) {
			recursive(root->left, retVec, path, sum, cur);
		}
		if (root->right != NULL) {
			recursive(root->right, retVec, path, sum, cur);
		}
		path.pop_back();
		cur -= root->val;
	}
};
int _tmain(int argc, _TCHAR* argv[])
{
	TreeNode* root = new TreeNode(10);
	TreeNode* rootLeft = new TreeNode(5);
	TreeNode* rootRight = new TreeNode(12);
	TreeNode* leftLeft = new TreeNode(4);
	TreeNode* leftRight = new TreeNode(7);

	root->left = rootLeft;
	root->right = rootRight;
	rootLeft->left = leftLeft;
	rootLeft->right = leftRight;

	Solution s;
	s.FindPath(NULL, 22);
	return 0;
}