#include"stdio.h"
double f(int n)
{
int i;
double k=1;
for(i=1;i<=n;i++)
k*=i;
return k;
}
main()
{
double n,m,cmn;
printf("Please input m and n:\n");
scanf("m=%lf,n=%lf",&n,&m);
if(n>=m)
printf("cmn=%lf\n",f(n)/(f(n-m)*f(m)));
else
printf("Error!");
}
帮我改改咯