67分。。。
#include <bits/stdc++.h>
#define int long long
#define endl "\n"
using namespace std;
int n,k;
int p[20];
signed main()
{
	cin>>n>>k;
	for(int i=1;i<=n;i++) p[i]=i;
	do{
		for(int i=1;i<=k;i++) {
			cout<<p[i]<<" ";
		}
			cout<<endl; 
	}while(next_permutation(p+1,p+1+n));	
}