P1088-火星人

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 #define _for(i,a,b) for(int i = (a);i < b;i ++)
 4 const int maxn = 10009;
 5 typedef long long ll;
 6 int N,M;
 7 int a[maxn];
 8 inline ll read()
 9 {
10     ll ans = 0;
11     char ch = getchar(), last = ‘ ‘;
12     while(!isdigit(ch)) last = ch, ch = getchar();
13     while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - ‘0‘, ch = getchar();
14     if(last == ‘-‘) ans = -ans;
15     return ans;
16 }
17 inline void write(ll x)
18 {
19     if(x < 0) x = -x, putchar(‘-‘);
20     if(x >= 10) write(x / 10);
21     putchar(x % 10 + ‘0‘);
22 }
23 
24 int main()
25 {
26     N = read(),M = read();
27     _for(i,0,N)
28         a[i] = read();
29     do
30     {
31         if(M==0)
32             break;
33         M --;
34     }while(next_permutation(a,a+N));
35     _for(i,0,N)
36     {
37         write(a[i]);
38         if(i!=N-1)
39         printf(" ");
40     }
41     return 0;
42 }