c - Working With Floats and Integers

Question

I've created an ATM like program which holds the money in a person's account. When the person takes out a withdrawal, it subtracts the withdrawal from the account along with a .50 surcharge. The problem I'm having is working with both integers and floats in this program. I converted the integer account to a floating point number but I get an error message when I try to print out the statement. Can someone tell me what I'm doing wrong?

#include <stdio.h>

int main (void) {
    int account = 2000;
    int withdrawal;
    float charge = 0.50;

    printf ("How much money would you like to take out? ");
    scanf ("%i", &withdrawal);

    while (withdrawal % 5 != 0) {
        printf ("Withdrawal must be divisible by 5. ");
        scanf("%i", &withdrawal);
    }

    account = ((float) account - charge) - withdrawal;

    printf("Remaining account: %.2f
", account);

    return 0;
}

Answer 1

int account = 2000;
printf("Remaining account: %.2f
", account);

This is wrong; it should be "%d" for integer, or better, change your account variable type to something that could represent the 0.50 you're surcharging. I don't recommend you to using (imprecise) floats for money either. You don't want to withdraw 10.499999997 when you meant 10.5. You need to think about the precision and rounding rules you'd use. AFAIK these are both mandated by laws or something.