# <compare>

**[<compare>](https://en.cppreference.com/w/cpp/header/compare)** provides the three-way comparison operator `<=>` (spaceship operator) and comparison result types (`std::strong_ordering`, `std::weak_ordering`, `std::partial_ordering`) introduced in C++20. It allows you to define a single `operator<=>` that automatically generates `==`, `!=`, `<`, `>`, `<=`, `>=`.

Use it to reduce boilerplate when a type needs rich comparison semantics.

## Example

This example uses the defaulted spaceship operator to automatically derive all comparison operators for a Point struct.

```cpp
// compile: g++ -std=c++20 -o compareexample compareexample.cpp
// run: ./compareexample
// description: three-way comparison with spaceship operator

#include <compare>
#include <iostream>

struct Point {
    int x, y;
    
    auto operator<=>(const Point& other) const = default;
};

int main() {
    Point p1{1, 2};
    Point p2{1, 3};
    
    if (p1 < p2) {
        std::cout << "p1 < p2 (automatically derived)\n";
    }
    
    return 0;
}
```