#include<stdio.h>
int main()
{
    int n;
    long long factorial = 1;
    if(scanf("%d", &n)!= 1)
    return 0;
    if(n<0){
        printf("Invalid input");
        return 0;
    }
    else {
        for (int i = 1; i<=n;i++)
        factorial *=i;
    }
    printf("%lld,factorial");
    return 0;
}