>>667
1.2

#include <stdio.h>
int fact2(int n, int m) {
    int i,ret=1;
    if(n>=m)for(i=0;i<m;i++)ret*=n-i;
    return ret;
}
int main(void) {
    int n,m;
    printf("calculate C(n,m)\n");
    printf("n ? "); scanf("%d",&n);
    printf("m ? "); scanf("%d",&m);
    printf("C(n,m) = %d\n",fact2(n,m)/fact2(m,m));
    return 0;
}