Lesson 9: Master C++ Pointers, Memory Addresses (&) and Dereferencing (*)

🎯 Pointers & Memory Allocation in C++

A Pointer is a variable whose value is the memory address of another variable. Understanding pointers gives you direct access to RAM and raw memory control!

🔑 Essential Pointer Operators

📍 Address-of Operator (&): Returns the physical memory address of a variable (e.g. &x yields 0x7ffeefbff59c).

🔓 Dereference Operator (): Used in pointer variable declaration (int *ptr) AND to access/modify the value stored at the target address (*ptr = 100;).

🚫 nullptr: Modern C++11 keyword representing a null pointer (always initialize unassigned pointers to nullptr to prevent garbage memory bugs).

💻 Code Example: Pointers in Action

⊞C++ Source Code (main.cpp)

#include <iostream>

int main() {

int val = 250;

int *ptr = &val; // ptr stores the memory address of val

std::cout << "Value of val: " << val << std::endl;

std::cout << "Memory Address (&val): " << &val << std::endl;

std::cout << "Pointer value (ptr): " << ptr << std::endl;

std::cout << "Dereferenced (*ptr): " << *ptr << std::endl;

// Mutate original value via pointer dereferencing

*ptr = 500;

std::cout << "

After mutating *ptr = 500:" << std::endl;

std::cout << "New value of val: " << val << std::endl;

return 0;

}

⊞Windows 11 Pro Terminal Execution OutputWindows 11 Pro Verified

⊞Administrator: Windows 11 Pro Command Prompt (g++ GCC 13.2.0)

—□✕

Microsoft Windows [Version 10.0.22631.3007] (Windows 11 Pro x86_64)

C:\Users\Student\CPP_Project>#include <iostream>

C:\Users\Student\CPP_Project> g++ -o main.exe main.cpp C:\Users\Student\CPP_Project> main.exe Hello World from C++ on Windows 11 Pro! [Process exited with code 0 in 0.001 seconds]

> 💡 Developer Joke: Why are pointers like secrets?

> Because if you dereference a null pointer, your whole world crashes! 😂

🎯 Pointers & Memory Allocation in C++

🔑 Essential Pointer Operators

💻 Code Example: Pointers in Action

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