Environment Setup

Before we start writing C++ code, we need to set up our “kitchen” first. A chef needs a stove, pans, and knives — a programmer needs a text editor and a compiler.

The good news: you have several options, from the easiest to the most comprehensive. Let’s go through each one.

Option 1: The Website Playground (Recommended!)

The playground is a code editor embedded right in this website. You can write C++ code, run it, and see the results — all on one page, without installing any software.

Why is the playground recommended for beginners?

• Zero setup — no downloads or installations needed
• Instant start — open your browser, write code, click Run
• Safe — code runs in an isolated environment, nothing on your computer can break
• Optimized — syntax highlighting, clear error messages
• Mobile-friendly — learn anywhere, even from your phone

You’ll learn how to use the playground in detail in the next lesson. For now, try running your first program:

#include <iostream>

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

If you see Hello, World! in the output area — congratulations! You just ran your first C++ program!

Don’t understand the code yet? That’s perfectly fine! We’ll break down every line in Unit 1. What matters right now is that you can run it.

Option 2: Install on Your Computer (Windows)

If you want a more “serious” setup on your own machine, you can install a C++ compiler locally. This gives you full control and works without an internet connection.

Option A: MSYS2 + MinGW (Recommended for Windows)

MSYS2 is an environment that provides the GCC/G++ compiler for Windows.

Steps:

1. Download MSYS2 from msys2.org
2. Install — run the installer and follow the prompts (use the default location C:\msys2)
3. Open the MSYS2 terminal that was just installed
4. Update the package manager:

   pacman -Syu

   (If prompted to close the terminal, close it, reopen, and run the command again)
5. Install the C++ compiler:

   pacman -S mingw-w64-ucrt-x86_64-gcc

6. Add to PATH:
   • Open Windows Settings → System → About → Advanced system settings
   • Click “Environment Variables”
   • Under “System variables”, find Path, click Edit
   • Add: C:\msys2\ucrt64\bin
   • Click OK on all dialogs
7. Verify installation — open a new Command Prompt and type:

   g++ --version

   If GCC version info appears, the installation was successful!

Option B: Visual Studio Community (Windows Alternative)

Microsoft Visual Studio Community is a full IDE that includes the C++ compiler (MSVC).

1. Download from visualstudio.microsoft.com
2. During installation, check “Desktop development with C++”
3. Wait for the download to complete (can be 5-10 GB)
4. Open Visual Studio, create a new project → Console App (C++)

How to Compile and Run from the Terminal

After installing a compiler, here’s how to run a C++ program from the terminal:

1. Create a file named hello.cpp using any text editor (Notepad, VS Code, etc.):

   #include <iostream>
   
   int main() {
       std::cout << "Hello from my computer!" << std::endl;
       return 0;
   }

2. Open a terminal (Command Prompt / PowerShell) and navigate to the folder where the file is saved:

   cd C:\Users\YourName\Documents

3. Compile:

   g++ hello.cpp -o hello

   This translates hello.cpp into a program called hello.exe.

4. Run:

   hello

   or

   ./hello

If everything works, you’ll see:

Hello from my computer!

Recommended Text Editors

If you’re coding locally, use a text editor with syntax highlighting (color-coded keywords) to make code easier to read:

• Visual Studio Code (VS Code) — free, lightweight, great C++ extensions. Download from code.visualstudio.com. Install the “C/C++” extension by Microsoft.
• Notepad++ — very lightweight, great for lower-spec computers
• Sublime Text — fast and elegant

Option 3: Online Compilers

If you can’t install software but want an alternative to this website’s playground, there are several online compilers available:

OnlineGDB

• Go to onlinegdb.com
• Select C++ from the language dropdown in the top right
• Write your code in the editor
• Click Run

Compiler Explorer (Godbolt)

• Go to godbolt.org
• More advanced — lets you see the assembly output
• Great for learning how compilers work under the hood

Replit

• Go to replit.com
• Create an account (free)
• Create a new Repl with the C++ template
• Full IDE in your browser

Comparison of Options

The Programming Workflow

Regardless of which environment you choose, the basic programming workflow is always the same:

Write Code  →  Compile  →  Errors?  →  Yes → Fix → Compile again
                              ↓
                             No
                              ↓
                           Run  →  Output correct?  →  No → Fix code
                                        ↓
                                       Yes
![Programming workflow diagram: write, compile, debug, run, done](/images/workflow-diagram.svg)
                                        ↓
                                      Done!

Don’t worry if you encounter errors frequently — that’s completely normal. Even experienced programmers spend a lot of time debugging (finding and fixing errors). The key: read error messages carefully — the compiler usually tells you which line the problem is on.

Summary

• The website playground is the fastest way to start learning
• Local installation (MSYS2/MinGW) is ideal if you want a more serious setup
• Online compilers serve as a backup when other options aren’t available
• The programming workflow: write → compile → debug → run → repeat
• Errors are normal and are part of the learning process

In the next lesson, we’ll take a tour of this website’s playground so you know all its features and are ready to start coding!