Tutorial: Hello World In C++

Code:

// Hello World In C++

#include <iostream>
using namespace std;

int main(int nNumberofArgs, char* pszArgs[])
{
    cout << "Hello world!";

    system("PAUSE");
    return 0;
}

Code:

// Hello World In C++

Is a comment - these are ignored by the compiler.

Code:

#include <iostream>

This tells the compiler to include the iostream library into the file. This is one of the most commonly used C++ libraries.

Code:

using namespace std;

Most programs in C++ require this line - everything in the standard C++ library is declared within what is called a namespace.

Code:

int main(int nNumberofArgs, char* pszArgs[])

This looks very confusing, but don't worry about it too much for now. All programs need this - the code starts executing when it sees the main() function.

Code:

cout << "Hello World!";

This statement writes "Hello World!" to the screen. The "cout <<" part is located inside the iostream, that's why we needed to include it.

Code:

system("PAUSE");
return 0;

These two lines make sure the user can see the results. If they weren't there, then the program would close as soon as you started it up!



You will notice a few things about how the program is laid out. Here's why it's all done.

- Semicolons at the end of each statement. You need them otherwise the program won't know when the statement is finished!

- Curly brackets ( { } ). These simply mark the beginning and end of the main() function.

- Indentation. It's not entirely necessary, but it helps a lot with finding errors when you write more complex programs.



You can't run your program unless you have a compiler. Luckily, there are loads of compilers out there, including a lot of free ones.

I would recommend Dev-C++. You can download it here, and their official website is here