Simple Program in C++

A simple C++ program basically consists of the following parts −

Basic structure of C++ program

#include <iostream.h>

int main() {

    return 0;
}

#include <iostream.h>

int main() {

return 0;

}

Above shown the basic structure of C++ program.

For every program we have to writeabove mention basic structure.

We can write or print in C++ language by using “cout” object.

It is used to display the output to the standard output device i.e. monitor.

In C++, cout is an object of class ostream. for example: code to write “hello” is as follows:

cout << “hello”;

In “cout” , “c” refers to “character” and ‘out’ means “output”, means cout refers “character output”.

cout object is used along with the insertion operator (<<) for display a stream of characters.

#include <iostream>

int main()
{
  /*  first C++ program */

  cout << "Hello World!";

return 0;
}

#include <iostream>

int main()

{

/* first C++ program */

cout << "Hello World!";

return 0;

}

OUTPUT

Hello World!

1	Hello World!

Description

First line #include <iostream.h> is a preprocessor, which instruct to C++ compiler to include iostream.h file. iostream ( input output stream ) header file contains definitions of objects like cin, cout etc.
int main() is the main function from where the program execution begins.
/*………..*/ is a “comments” in the program. This comments will be ignored by the compiler during execution of program
cout is an object of ostream in C++ which is used to print message.
line return 0; terminates the main() function and returns the value 0.return 0 tells the compiler that everything is ok and the execution of main() function ends. Because 0 is the code for successful execution, while values greater than 0 (integers) is an indication that something went wrong.