#include <stdio.h>

int main (void) {
    long input;
    long N = 1;
    
    scanf("%d", &input);
    
    if (input < 50) {
        for (long i = input; i >= 1; i--) {
            N =  N * i % (long)1e12;
        }
        
        printf("%012ld\n", N);
    }
    else {
        printf("000000000000\n");
    }
    
    
    
    return 0;
}