C++ allocator sample

allocator sample.txt

#include <cstdlib>

template <class T>
struct MyAllocator {
    using value_type = T;
    
    // default constractor
    // copy constractor
    // move constractor
    MyAllocator()
    {
    }
    
    template <class U>
    MyAllocator(const MyAllocator<U>&)
    {
    }
    
    T* allocate(std::size_t n)
    {
        return reinterpret_cast<T*>(std::malloc(sizeof(T) * n));
    }
    
    void deallocate(T* p, std::size_t n)
    {
        static_cast<void>(n);
        std::free(p);
    }
};

// compare operator
template <class T, class U>
bool operator==(const MyAllocator<T>&, const MyAllocator<U>&)
{
    return true;
}

template <class T, class U>
bool operator!=(const MyAllocator<T>&, const MyAllocator<U>&)
{
    return false;
}


#include <vector>
#include <list>
int main()
{
    std::vector<int, MyAllocator<int>> v = {1, 2, 3};
    std::list<int, MyAllocator<int>> ls = {4, 5, 6};
}