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
|
#include <vector>
using std::vector;
void combine1(int start, int end, int rest_select_count, vector<int> &head, vector<vector<int>> &result)
{
if (rest_select_count == 0)
{
for (int i = start; i < end; i++)
{
head.push_back(i);
result.push_back(head);
head.pop_back();
}
return;
}
for (int i = start; i < end - rest_select_count; i++)
{
head.push_back(i);
combine1(i + 1, end, rest_select_count - 1, head, result);
head.pop_back();
}
}
class Solution
{
public:
vector<vector<int>> combine(int n, int k)
{
vector<vector<int>> result;
vector<int> head;
combine1(1, 1 + n, k - 1, head, result);
return result;
}
};
int main()
{
Solution s;
auto result = s.combine(20, 16);
return 0;
}
|
