As people said that if return return any other value not 0 that means it's an error. Checkout this code it knew my error.

Question

https://code.sololearn.com/c5lsospbfEWs/?ref=app

Answer 1

The unknown 321

First thing the statement is applicable to a running program. Your code does not even compile ! What do you expect from a compiler to not even tell you the syntax errors in your code?

What do you mean by this ?

Answer 2

The second thing you said about the non zero return is an indication of failure for system. I already know this.
Can you explain the return logically with some examples please ?

Answer 3

Check out the code that I wrote. If you did then what I need to know is when should I use return statement ?. Because some people use differently like in calculation