순열(15649), 조합(15650) (c++)

순열 구현 문제

https://www.acmicpc.net/problem/15649

15649번: N과 M (1)

#include<iostream>
#include<vector>
#include<algorithm>

using namespace std;

int n, m;

int arr[9] = {};
bool visited[9] = {};

void dfs(int depth) {
	if (depth == m) {
		for (int i = 0; i < m; i++) {
			cout << arr[i] << " ";
		}
		cout << "\n";
		return;
	}
	for (int i = 1; i <= n; i++) {
		if (!visited[i]) {
			visited[i] = true;
			arr[depth] = i;
			dfs(depth + 1);
			visited[i] = false;
		}
	}
}
int main() {

	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);

	cin >> n >> m;
	dfs(0);

	return 0;
}

조합 구현 문제

https://www.acmicpc.net/problem/15650

15650번: N과 M (2)

#include<iostream>
#include<vector>
#include<algorithm>

using namespace std;

int n, m;

int arr[9] = {};
bool visited[9] = {};

void dfs(int depth, int num) {
	if (depth == m) {
		for (int i = 0; i < m; i++) {
			cout << arr[i] << " ";
		}
		cout << "\n";
		return;
	}
	for (int i = num; i <= n; i++) {
		if (!visited[i]) {
			visited[i] = true;
			arr[depth] = i;
			dfs(depth + 1,i+1);
			visited[i] = false;
		}
	}
}
int main() {

	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);

	cin >> n >> m;
	dfs(0,1);

	return 0;

}