```cpp
#include <iostream>
#include <functional>

std::function<int()> fibonacci()W
{
    int current = 1, next = 1;

    return [=]() mutable {
        int result = current;
        next = current + (current = next);
        return result;
    };
}

int main()
{
    auto fib = fibonacci();

    for (int i = 0; i < 10; i++) {
        std::cout << fib() << std::endl;
    }

    return 0;
} 

```