Lecture 9: Pointers, Dynamic Memory & Linked Lists

Heap Memory Visualization

int* p = new int(42);
// ...
delete p;

struct Node {
    int data;
    Node* next;
};

Node* head = nullptr;  // Empty list

Q1. Which is the correct way to allocate an array of 10 integers in C++?

int arr = new int(10);
int* arr = new int[10];
int arr[10] = new int;

Q2. What happens if you forget to `delete` dynamically allocated memory?

Program crashes immediately
Memory becomes read-only
Memory leak occurs

Dynamic memory (`new`/`delete`) allows flexible sizing at runtime.
Forgetting to `delete` causes memory leaks. Accessing memory after `delete` is undefined behavior.
Modern C++ strongly prefers smart pointers (`std::unique_ptr`) to automate memory management and prevent these errors.
Linked lists are a fundamental dynamic data structure built with nodes and pointers.