#include <stdio.h>
#include <stdlib.h>

/*
 * factorials
 *
 * in both for loop, as well as recursive
 * factorial: voor int i, vermenigvuldig dan elke i to je bij 1 komt (uit gaande van positive ints)
 *
 * dus, f(3)=3*2*1 = 6 ; f(4)=4*3*2*1=24 ; f(a)=no ; f(-2)= no ; f(2.1) = no
 *
 * will use 2 functions:
 * recfac using recursion
 * itfac using iteration
 *
 * should probably figure out how to test this? maybe a dumb K:V?
 * *  */

int recfact(int input){
    int fac = 1;
    if (input==1) {
        return fac;
    }
    else {
        fac *= input * recfact(input-1);
    }
}

int itfact(int input){
    int sum = 1;
    for (int i = 1; i <= input; i++) {
        sum *= i;
    }
    return sum;
}

int main(){

    int input = 5;

    //recfact(input);
    //itfact(input);
    printf("%d\n", recfact(input));
    printf("%d\n", itfact(input));
    return 0;
}