Hello world with c++
#include<iostream>:
Is a processing directive that includes the content of the standard
c++header file iostream.
iostream
is a standard library header file that contains definitions
of standard
input and output streams.
The standard input /output streams provide
the way to get input /give output to an external system(usually
terminal).
int main(){...}:
It defines a new function with the name main, by
convention the main function is called upon the execution of the program.
And
there should be only one main function in a c++ program. and it must
always return an integer.
Here the int in front of main ()/or any function defines
the data type which the function gonna return.
note: as the main
function is the heart of the program, the value returned by the main
function is an exit code.
return 0-->EXIT_SUCCESS
any other return code -->associated with an error
in
the above example, we didn't have mentioned any return statement, that's
because the main function will return 0 by default if we didn't mention any
return specifically.
note:
In C++ all functions other than the one with void data
type should return a value according to the functions data type. or not
return at all. it can only return the value based on the function's data
type.
std::cout << "Hello World!" << std::endl;
prints "Hello World!" to the standard output stream:
std is a namespace and:: is the scope of the
resolution operator.
here we used:: to
mention that we want to use cout from the
std namespace.