This is part of code from my greedy.c

The purpose of this do while loop is to get a valid input.

I'm having trouble, I tested it outside do while loop and it was working fine.

I think that mistake is really dumb but I really need help!!

I'm stuck here... :-(

void calc(int number, int change, int coins)
{
    int result = change / number;
    coins = coins + result;
    change = change % number;
}

int main(void)
{      
    int change;

    do
    {
        printf("How much I owe you: ");
        change = round(GetFloat() * 100);
    } 
    while (change < 0);

    int coins = 0;

    while (change > 0)
    {
        if (change >= 25)
        {
            calc(25, change, coins);    
        }

        if (change >= 10)
        {
            calc(10, change, coins);  
        }

        if (change >= 5)
        {
            calc(5, change, coins);
        }

        if (change >= 1)  
        {
            calc(1, change, coins);
        }
    }

    printf("Minimum number of coins needed is: %i \n", coins);
    return 0;
}