Factorial - C

#include <stdio.h>

//function definition
int factorial(int num) {

    if (num == 1)  /* base case */
        return (1);
    else
        return (num * factorial(num - 1));
}

int main() {
    int x;
    scanf("%d", &x);

    printf("The factorial of %d is %d\n", x, factorial(x));

    return 0;
}