2-9

#include<stdio.h>
int main(void)
{
    int i,n;
    double product;          

    printf("Enter n:");      
    scanf("%d",&n);         
    product=1;               
    for(i=1;i<=n;i++){      
        product=product*i;
    }
    printf("product=%.0f\n",product);     


    return 0;
}