ATM problem to slow?

int cash,balance;
float saldo;
scanf("%d",&cash);
scanf("%d",&balance);

if(cash%5!=0 || cash+0.5>balance){
    printf("%d",balance);
    return 1;
}

else
    saldo=balance-cash-0.5;
    printf("%.2f",saldo);
    return 3;

My solution seems to be too slow. Any ideas?