hdu 1027 输出第m个全排列（next_permutation）

Sample Input
6 4 //输出第4个全排列
11 8

Sample Output
1 2 3 5 6 4
1 2 3 4 5 6 7 9 8 11 10

 

# include <cstdio>
# include <iostream>
# include <algorithm>
using namespace std ;

int a[2000] ;

int main ()
{
    int n , m ;
    while (scanf("%d %d" , &n , &m) != EOF)
    {
        int i ;
        for (i = 1 ; i <= n ;i++)
           a[i] = i ;
        int num = 1 ;
        while (num < m)
        {
            next_permutation(a+1 , a+1+n) ;
            num++ ;
        }
        for (i = 1 ; i <= n-1 ;i++)
          printf("%d " , a[i]) ;
        printf("%d\n",a[n]) ;
    }
}