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

int main(void)
{
    int coinsReturned = 0;

    printf("How much change is owed? \n");
    float change = get_float();

    while (change < 0) {
        printf("How much change is owed? \n");
        change = get_float();
    }


    int amount =  round(change * 100);

    while (amount > 0) {
        if ((amount - 25) >= 0) { amount = amount - 25; coinsReturned++; }
        else if ((amount - 10) >= 0) { amount = amount - 10; coinsReturned++; }
        else if ((amount - 5) >= 0) { amount = amount - 5; coinsReturned++; }
        else if ((amount - 1) >= 0) { amount = amount - 1; coinsReturned++; }
    }

    printf("%d coins\n", coinsReturned);
}