Notes.txt

Preprocessors -  In C++,  all lines that start with pound (#) sign are called directives and are processed by preprocessor which is a program invoked by the compiler.

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Q. Is it fine to write “void main()” or “main()” in C/C++?
Ans - 
No. A conforming implementation accepts : 

1. int main()
   { /* ... */ }

2. int main(int argc, char* argv[])
   { /* ... */ }

Even if your compiler accepts “void main()” avoid it, or risk being considered ignorant by C and C++ programmers. 
You can even specify main() without any return type like :

#include <iostream> 
main()
{ /* ... */}

If you write the whole error-free main() function without return statement at the end then compiler automatically add return statement with proper datatype at the end of the program.

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