Overview

Writing your first C++ program is an exciting step into the world of software development. In this post we will guide you through the process of writing and running your first C++ program.

Step 1: Setting Up Your Environment

Before you can start coding, you need a development environment. Here's what you will need:

A C++ Compiler:

You can use popular C++ compilers like GCC (GNU Compiler Collection), Clang or Microsoft Visual C++ depending on your operating system. For this course I will be using the GCC in Ubuntu linux.

Installing GCC via Command Line in Ubuntu:

1. Open a terminal window. You can do this by pressing Ctrl+Alt+T or by searching for Terminal in the Ubuntu application launcher.
2. Update the package list to ensure you have the latest information about available packages and their version:
   sudo apt update
3. Install GCC by running the following command:
   sudo apt install gcc
   or installing GCC for C++ development (this will install GCC and g++ both):
   sudo apt install g++
   or installing additional tools which includes essential build-tools, libraries, GCC and g++.
   sudo apt install build-essential
4. During the installation, Ubuntu may ask for your password to confirm that you have the necessary privileges. Enter you password and press Enter to continue.
5. Once the installation is complete, you can verifiy the installed version of GCC by running:
   gcc --version
   This command will display the installed GCC version.

A Text Editor or Integrated Development Environment (IDE):

You can use a simple text editor or a code-focused IDE like Visual Studio Code.

Step 2: Writing Your First C++ Program

Let's start with quintessential “Hello, World” program. This simple program displays the text “Hello, World” on your screen.

#include <iostream>

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

Here's what happening in this program:

• “#include <iostream>”: This line includes the iostreamlibrary, which allows us to use input and output functions.
• “int main()”: Every C++ program has a main function. It's where the program start executing.
• “{ }”: These curly braces enclose the body of the main function, where you put your code.
• 'std::cout << “Hello, World” << std::endl;': This line used std::cout to print Hello, World to the console. std::endl adds a newline character, so that next cout statement start printing from next line.
• “return 0;”: This line indicates that the program has executed successfully. The 0 means it exited without errors.

Step 3: Compiling and Running Your Program

Now that you have written your code, it's time to compile and run it.

1. Save your file with a .cpp extension, for example, hello.cpp.
2. Open your terminal or command prompt and navigate to the directory where your file is located.
3. Compile your program using the C++ compiler. For example, as we installed g++, so we be using it:
   g++ hello.cpp -o hello
   This command complies hello.cpp and generates an executable file named hello.
4. Run your program:
   ./hello

You should see the output:

Hello, World