leetcode/algorithms/PathSum2/solve.cpp at master · int32bit/leetcode · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
struct TreeNode {
    int val;
    TreeNode *left;
    TreeNode *right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};
class Solution {
public:
    vector<vector<int> > pathSum(TreeNode *root, int sum) {
	    vector<vector<int>> result;
	    vector<int> t;
	    pathSum(result, t, root, sum);
	    return result;
    }
private:
    void pathSum(vector<vector<int>> &result, vector<int> cur, TreeNode *root, int sum) {
	    if (root == NULL)
		    return;
	    cur.push_back(root->val);
	    sum -= root->val;
	    if (isLeft(root) && sum == 0) {
		    result.push_back(cur);
		    return;
	    }
	    pathSum(result, cur, root->left, sum);
	    pathSum(result, cur, root->right, sum);
    }
    bool isLeft(TreeNode *p) {
	    if (p == nullptr)
		    return false;
	    return p->left == nullptr && p->right == nullptr;
    }
};
TreeNode *mk_node(int val)
{
	TreeNode *p = new TreeNode(val);
	return p;
}
void mk_child(TreeNode *root, TreeNode *left, TreeNode *right)
{
	root->left = left;
	root->right = right;
}
void mk_child(TreeNode *root, int left, int right)
{
	mk_child(root, mk_node(left), mk_node(right));
}
int main(int argc, char **argv)
{
	Solution solution;
	TreeNode *root = mk_node(5);
	mk_child(root, 4, 8);
	TreeNode *left = root->left;
	TreeNode *right = root->right;
	mk_child(left, mk_node(11), nullptr);
	mk_child(left->left, 7, 2);
	mk_child(right, 13, 4);
	mk_child(right->right, 5, 1);
	auto result = solution.pathSum(root, 22);
	cout << "size: " << result.size() << endl;
	for (auto v : result) {
		for_each(v.begin(), v.end(), [](int i){cout << i << " ";});
		cout << endl;
	}
}