#include <memory>
#include <iostream>

class Entity {
public:
    Entity()          { std::cout << "Entity created\n"; }
    ~Entity()         { std::cout << "Entity destroyed\n"; }
};

int main() {
    // Modern & safe way (C++14+)
    auto ptr = std::make_unique<Entity>();      // constructor runs

    // Use like raw pointer
    // ptr->DoSomething();

    // Transfer ownership
    auto ptr2 = std::move(ptr);                 // ptr now nullptr

}   // ptr2 dies → "Entity destroyed" printed automatically

What is Reference Counting 

Imagine an object (like an Entity) is a toy.

Every time someone wants to "use" the toy, they take a ticket (a shared_ptr).
Every ticket increases a counter by 1 ("Hey, one more person is holding this toy").
When someone is done with the toy, they throw away their ticket → counter decreases by 1.
When the last ticket is thrown away (counter reaches 0), the toy is automatically destroyed (deleted).

That counter is the reference count.


How shared_ptr Does It

#include <memory>
#include <iostream>

class Entity {
public:
    ~Entity() { std::cout << "Entity destroyed\n"; }
};

int main() {
    std::cout << "Start\n";

    auto s1 = std::make_shared<Entity>();          // ref count = 1

    {
        auto s2 = s1;                              // ref count = 2
        auto s3 = s2;                              // ref count = 3

        std::cout << "Inside block – ref count: " << s1.use_count() << "\n";
    }                                              // s2 & s3 die → ref count = 1

    std::cout << "After block – ref count: " << s1.use_count() << "\n";

}  // s1 dies → ref count = 0 → "Entity destroyed" printed automatically