#include<stdio.h>
double fact(int n);
int main()
{
int m,n;
int a,b,c;
double result;
printf("Please enter m:");
scanf("%d",&m);
printf("Please enter n:");
scanf("%d",&n);
a=fact(m);
b=fact(n);
c=fact(n-m);
printf("the result is:%.2f",b/(a*c));
return 0;
}
double fact(int n)
{
int i;
double product;
product=1;
for(i=1;i<=n;i++)
{
product=product*i;
}
return product;
}