hello-world-first-cpp-program.md

Hello world first C++ program

Create a new file named main.cpp

#include <iostream>

int main() {
    std::cout << "Hello Gitpod World" << std::endl;
    return 0;
}

Program breakdown

#include <iostream>

This is known as a preprocessor directive and begins with # no semi-colon ; is needed at the end.

int main() 
{
    // main fucntion code here
}

The main function is the entry point to the program.

std::cout << "Hello Gitpod World" <<

Use namespace std, cout to output to the console.

Insertion operator << is use to insert into cout.

"Hello Gitpod World"

The text to display on screen should be placed inside double quotes. This is known as a string literal.

<< std::endl;

Inserts to cout a new line, using the namespace std, endl to output to the console.

Compile file main.cpp to create new file a.out

Check your compile version:

$ g++ --version

g++ (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
Copyright (C) 2021 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Open terminal and type:

$ g++ -Wall -std=c++14 main.cpp

Execute file a.out

$ ./a.out

Expected output

$ ./a.out
Hello Gitpod World
$