This is a simple calculator which later on is going to motivate users to try and do the math themselves by becoming more and more honest with them. For example, if they need to do calculations with multidigit numbers, that, okay, might be tricky, so the calculator won't be very hard on them and just solve it. However, if the equation is a simple sum of two integers like 2 + 3, maybe it should suggest solving it themselves. Even worse, if it's multiplication by one or zero, that is just of the line! After all, it's a competition organized by the International Union Against Idleness.