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# C++ Rule of zero

**[Rule of zero](https://en.cppreference.com/w/cpp/language/rule_of_zero)** states that if a class manages resources correctly via [[raii|RAII]], it should define no special member functions at all—not destructor, copy constructor, copy assignment, move constructor, or move assignment. The compiler's defaults work correctly when members are themselves RAII-compliant (e.g., `unique_ptr`, `vector`, `string`).

Prefer the rule of zero by using standard library containers and smart pointers instead of manual resource management.

## Example

This example shows how using standard library types makes manual special members unnecessary.

```cpp
// compile: g++ -o rule_zero rule_zero.cpp
// run: ./rule_zero
// description: rule of zero: no special members needed with standard containers

#include <iostream>
#include <vector>
#include <memory>

class Container {
private:
    std::vector<int> data;
    std::unique_ptr<int[]> buffer;
public:
    Container(size_t n) : buffer(std::make_unique<int[]>(n)) {}
    
    // No destructor, copy constructor, copy assignment, move constructor, or move assignment needed
    // Compiler-generated versions work correctly due to RAII members
};

int main() {
    Container c1(100);
    Container c2 = std::move(c1);  // move works correctly
    Container c3 = c2;              // copy works correctly
    
    return 0;
}
```