#include <stdio.h>

int faculteit_n(int n) {
    int i, res = 1;
    for (i = 1; i <= n; i = i + 1) {
        res = res * i;
    }
    return res;
} 

int faculteit(int n) {
    if (n > 0) 
        return n * faculteit(n - 1);
    return 1;
} 

int main(void) {
    int n;
    for (n = 0; n < 15; n = n + 1) {
        printf("%d! = %d\n", n, faculteit_n(n));
        printf("%d! = %d\n", n, faculteit(n));
    }
    getchar();
    return 0;
}