C++ Setup — Install GCC and Run First Program

What is C++?

C++ is a general-purpose, compiled, statically-typed programming language created by Bjarne Stroustrup in 1979 at Bell Labs as an extension of C. It adds object-oriented programming, generic programming (templates), and the Standard Template Library (STL) on top of C's procedural foundation.

C++ is used in operating systems, game engines, browsers, databases, embedded systems, and high-frequency trading - anywhere performance and control matter.

Why Learn C++?

Combines low-level memory control (like C) with high-level OOP abstractions
Powers game engines (Unreal Engine), browsers (Chrome), and databases (MySQL)
Foundation for understanding how languages like Java and C# work under the hood
Essential for competitive programming and systems programming
Modern C++ (C++11/14/17/20) is expressive and safe while remaining fast

Setting Up the Compiler

Platform	Compiler	Install	Verify
Windows	GCC (MinGW-w64)	mingw-w64.org or via VS Code C++ extension	`g++ --version`
Linux	GCC	`sudo apt install g++`	`g++ --version`
macOS	Clang (via Xcode)	`xcode-select --install`	`g++ --version`

Online: Use OnlineGDB or Compiler Explorer to run C++ without any local setup.

Structure of a C++ Program

#include <iostream> - includes the standard I/O library
using namespace std; - avoids writing std:: prefix everywhere
int main() - entry point of every C++ program
cout << - outputs to console (C++ stream syntax)
return 0; - signals successful execution

Hello World - First C++ Program

#include <iostream>   // standard input/output stream library
using namespace std;  // use std namespace - avoids std::cout

int main() {
    cout << "Hello, World!" << endl;  // endl = newline + flush
    cout << "Welcome to C++!" << "\n"; // \n is faster than endl
    return 0;  // 0 = success
}

Compile and Run

Step	Command	Description
Compile	`g++ hello.cpp -o hello`	Compile to executable named hello
Compile (C++17)	`g++ -std=c++17 hello.cpp -o hello`	Use C++17 standard
Run (Linux/Mac)	`./hello`	Run the program
Run (Windows)	`hello.exe`	Run on Windows
With warnings	`g++ -Wall -Wextra hello.cpp -o hello`	Enable all warnings (recommended)

C++ vs C - Key Differences

#include <iostream>
#include <string>   // C++ string class (not char array)
using namespace std;

int main() {
    // C++ uses cin/cout instead of scanf/printf
    string name;
    cout << "Enter your name: ";
    cin  >> name;
    cout << "Hello, " << name << "!" << endl;

    // C++ has bool type natively
    bool isLearning = true;
    cout << "Learning C++: " << boolalpha << isLearning << endl;

    // C++ supports // single-line comments (C99 also does)
    /* and multi-line comments */

    // C++ has references (C does not)
    int x = 10;
    int &ref = x;  // ref is an alias for x
    ref = 20;
    cout << "x = " << x << endl;  // 20

    return 0;
}