Why we write "int" before writing main()

Question

I see all places have something written before main(), like "void", "int"

Answer 1

This is because main() is still a function, and like all C++ functions, requires a return type. Typically, that is int or void, but it's recommended to use int so you can end the program early if necessary.

Answer 2

It's the result code for the parent process. Usually this is the operating system executor.

Answer 3

1) "void main" is not (and never was) standard C. Use only "int main"

2) You can end the program early even if you use "void main" :)) . But... don't use it :)

3) The return code goes back to the parent process (the one that actually launched your program)