Ending of function

Question

Why do certain functions need a
return 0;
At the end and other do not?

Answer 1

It's recommended to add return 0; to the end of the main method.
https://www.sololearn.com/discuss/259277/?ref=app
https://www.sololearn.com/discuss/200512/?ref=app

Answer 2

Function return values depends on their return type. Void functions, for example require no return value (void). Integer functions return integer value, boolean functions return boolean values, etc.