C++ Dynamic Memory Allocation: Heap Management, new/delete & Leak Prevention

Stack memory is fast but fixed in size. When your program needs to allocate memory whose size is only known at runtime (e.g., loading a 4K game texture or a 10,000-row database query), you must allocate memory dynamically on the Heap.

Figure 6: Program Memory Architecture: Stack (Automatic) vs Heap (Dynamic)

The new and delete Operators

#include <iostream>

int main() {
    // 1. Allocate a single integer on the Heap
    int* ptr = new int(250);
    std::cout << "Heap value: " << *ptr << "\n";

    delete ptr;         // Deallocate heap memory
    ptr = nullptr;      // Prevent dangling pointer!

    // 2. Allocate a dynamic array of integers on the Heap
    int size = 5;
    int* dynamicArr = new int[size]{10, 20, 30, 40, 50};

    // CRITICAL: Always use delete[] for arrays!
    delete[] dynamicArr;
    dynamicArr = nullptr;

    return 0;
}