杭电2048

 1 #include <stdio.h>

 2 float fac(int a)//阶乘

 3 {

 4     if(a==0)

 5         return 1;

 6     else

 7         return a*fac(a-1);

 8 }

 9 int main()

10 {

11     int t,i,num;

12     float p[50]={0,0,1};                    

13     scanf("%d",&t);

14     i=3;

15     while(t--)

16     {

17         scanf("%d",&num);

18         for(;i<=num;i++)

19             p[i]=(i-1)*(p[i-1]+p[i-2]);

20         printf("%.2f%%\n",p[num]*100/fac(num));

21     }

22     return 0;

23 }