http://acm.hdu.edu.cn/showproblem.php?pid=1570
#include<stdio.h>
void main()
{
int i,j,k,y,z,m,n;
long sum,sum1,sum3;
long sum2;
char x;
scanf("%d",&i);
for(j=0;j<i;j++)
{
sum3=sum=sum1=1;
scanf("%c%d%d",&x,&m,&n);
getchar();
if(x=='A')
{
for(k=1;k<=n;k++)
{
sum=sum*k;
}
if(n-m==0) sum1=1;
else
{
for(k=1;k<=(n-m);k++)
sum1=sum1*k;
}
sum2=sum/sum1;
}
else
{
for(k=1;k<=n;k++)
{
sum=sum*k;
}
if(n-m==0) sum1=1;
else
{
for(k=1;k<=(n-m);k++)
sum1=sum1*k;
}
for(k=1;k<=m;k++)
sum3=sum3*k;
sum2=sum/(sum3*sum1);
}
printf("%d\n",sum2);
}
}
高手帮忙下