백준 15650 c++

#include <iostream>
//다시 하기
using namespace std;

int n, m;
int arr[9] = { 0, };
bool visited[9] = { 0, };

int input(int lower, int upper)
{
	//cout << "input()" << endl;
	int A;

	while (1)
	{
		cin >> A;
		if (A >= lower && A <= upper)
		{
			break;
		}
		else
		{
			;
		}
	}

	return A;
}

void dfs(int num, int cnt)
{
	int i;

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

int main(void)
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);

	n = input(1, 8);
	m = input(1, n);
	dfs(1, 0);

	return 0;
}