# <memory>

**[<memory>](https://en.cppreference.com/w/cpp/header/memory)** provides smart pointers—`std::unique_ptr<T>` (exclusive ownership), `std::shared_ptr<T>` (reference-counted ownership)—and `std::make_unique`, `std::make_shared` factories. Smart pointers automatically delete memory via RAII, preventing leaks and use-after-free.

Use `std::unique_ptr` by default; use `std::shared_ptr` only when you need shared ownership semantics. Avoid raw `new`/`delete` in modern C++.

## Example

This example demonstrates exclusive ownership with unique_ptr and reference-counted ownership with shared_ptr, showing automatic cleanup.

```cpp
// compile: g++ -std=c++11 -o memoryexample memoryexample.cpp
// run: ./memoryexample
// description: smart pointers and automatic cleanup

#include <memory>
#include <iostream>

int main() {
    {
        auto ptr = std::make_unique<int>(42);
        std::cout << "unique_ptr value: " << *ptr << "\n";
    }
    
    auto sptr = std::make_shared<int>(99);
    {
        auto sptr2 = sptr;
        std::cout << "use_count: " << sptr.use_count() << "\n";
    }
    std::cout << "use_count after scope: " << sptr.use_count() << "\n";
    
    return 0;
}
```