How do I fix this to make the program work?

So it's supposed to scan xx.xx euro and if the money is less than the person has to pay, it prints a message asking them to pay <the remaining> more. The code is:

Code:

handed_in = 0; 
remaining = pay;

while (handed_in < pay) {
            scanf("%lf", &handed_in);
            remaining = remaining - handed_in;
            if (remaining > 0) {
                printf("PAY %5.2lf more \n", remaining);
            }
        }

After this, I'm covering the case according to which the person has paid more money than owed, in which case the change is provided.

THE PROBLEM IS: if I pay less the first time, and when asked to pay more, I pay MORE than asked, the program stops scanning and nothing happens. But if I do pay more the first time, things work OK.

So how do I go about this? Replying would mean the world to me.


example:
It says PAY 8.40.
I enter 3.
It says PAY 5.40 more.
I enter 3.
It says PAY 2.40 more.
I enter 3.
And nothing happens next. :/

You need to keep a running total of the amount handed in and compare that with pay, or check if remaining > 0 to control your loop. Right now, handed_in only tracks the amount handed in on that one payment.

Update: The following morning I just woke up and finished the algorithm, before even reading your answer. Looks like I could have used an 8-hour sleep before asking. You were obviously correct and thank you for replying.