递归实现排列型枚举

#include<iostream>
using namespace std;

const int N = 10;
int state[N];
bool used[N];
int n = 0;
void dfs(int u) 
{
	if (u > n) 
	{
		for(int i=1;i<=n;i++)
			printf("%d ", state[i]);
		printf("\n");
	}
	for (int i = 1; i <= n; i++)
	{
		if (!used[i])
		{
			state[u] = i;
			used[i] = true;
			dfs(u + 1);
			
			state[u] = 0;
			used[i] = false;
		}
	}

}
int main()
{
	scanf("%d", &n);
	dfs(1);
	return 0;
}