#include <stdio.h>
#include <cs50.h>
#include <math.h>

int main()
{
    float change_as_float;
    do
    {
        change_as_float = get_float("Change owed: ");
    }
    while (change_as_float < 0);

    /* re-cast change due from float to an integer in pennies */
    int change = round(change_as_float * 100);
    int total_coins = 0;
    int coins[4] = {25, 10, 5, 1};

    /* if quarters can be used
     * see how many quarters can be used by using division and then rounding the result
     * return the remainder using the modulo (%) operation
     * continue through the denominations one by one from highest value to lowest value */
    for (int i = 0; i < 4; i++) {
        total_coins += round(change/coins[i]);
        change = change % coins[i];
    }

    printf("%i\n", total_coins);
}