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#include <memory.h>
#include <iostream>
#include <limits>
#include <vector>

class A
{
public:
    A() 
    {
        std::cout << "A's constructor" << std::endl;
    };
    ~A()
    {
        std::cout << "A's destructor" << std::endl;
    }

    void* operator new(size_t allocSize)
    {
        std::cout << "A's simple operator new" << std::endl;
        return ::operator new(allocSize);
    }
    void* operator new(size_t allocSize, unsigned char initValue)
    {
        std::cout << "A's init value placement operator new" << std::endl;
        void * returnPointer = ::operator new(allocSize);
        memset(returnPointer, initValue, allocSize);
        return returnPointer;
    }
    void* operator new(size_t allocSize, void* ptr)
    {
        std::cout << "A's raw pointer placement operator new" << std::endl;
        return ptr;
    }

    void operator delete(void* ptr)
    {
        std::cout << "A's simple delete operator" << std::endl;
        ::operator delete(ptr);
        return;
    }
    void operator delete(void* ptr, unsigned char initValue)
    {
        std::cout << "A's init value placement delete operator" << std::endl;
        ::operator delete(ptr);
        return;
    }
    void operator delete(void* ptr, void* ptr2)
    {
        std::cout << "A's raw pointer placement delete operator" << std::endl;
        return;
    }
};

class B
{
public:
    B()
    {
        std::cout << "B's constructor." << std::endl;
    }
    B(const B&)
    {
        std::cout << "B's copy constructor." << std::endl;
    }
    ~B()
    {
        std::cout << "B's destructor." << std::endl;
    }
};

void* operator new(size_t allocSize)
{
    std::cout << "Customized global new operator." << std::endl;

    void* returnPointer = malloc(allocSize + sizeof(__int32));
    __int32* sizePointer = (__int32*)returnPointer;
    *sizePointer = (__int32)allocSize;
    return sizePointer + 1;
}

void operator delete(void* ptr)
{
    std::cout << "Customized global delete operator." << std::endl;
    __int32* orignalPointer = (__int32*)ptr - 1;
    free(orignalPointer);
    return;
}

template<typename T> class YaMemAlloc
{
public:

    // Type definitions.
    typedef T value_type;
    typedef value_type* pointer;
    typedef const value_type* const_pointer;
    typedef value_type& reference;
    typedef const value_type& const_reference;
    typedef std::size_t size_type;
    typedef std::ptrdiff_t difference_type;

    // Convert an allocator<T> to allocator<U>.
    template<typename U>
    struct rebind 
    {
        typedef YaMemAlloc<U> other;
    };

    // Ctor/Dtor.
    YaMemAlloc() throw() {};
    YaMemAlloc(const YaMemAlloc&) throw() {};
    template <class U> YaMemAlloc(const YaMemAlloc<U>&) throw() {};
    ~YaMemAlloc() throw() {};

    // Address.
    inline pointer address(reference r) { return &r; }
    inline const_pointer address(const_reference r) { return &r; }

    // Memory management.
    pointer allocate(size_type cnt, std::allocator<void>::const_pointer hint = 0)
    {
        return reinterpret_cast<pointer>(::operator new(cnt * sizeof (T))); 
    };
    void deallocate(pointer p, size_type)
    {
        ::operator delete(p); 
    };
    size_type max_size() const throw() 
    {
        return std::numeric_limits<size_type>::max() / sizeof(T);
    };

    // Placement new/delete.
    void construct(pointer p, const T& val) { new(p) T(val); }

    void destroy(pointer p) { p->~T(); }

    // Compare.
    template <typename U>
    bool operator==(YaMemAlloc<U> const&) { return true; };
    template <typename U>
    bool operator!=(YaMemAlloc<U> const& a) { return !operator==(a); };
};

//
//template <class T1, class T2>
//bool operator==(const allocator<T1>& a1, const allocator<T2>& a2) throw()
//{
//    return true;
//}
//
//template <class T1, class T2>
//bool operator!=(const allocator<T1>& a1, const allocator<T2>& a2) throw()
//{
//    return false;
//}

// Specilized for void
template<> class YaMemAlloc<void>
{
  typedef void        value_type;
  typedef void*       pointer;
  typedef const void* const_pointer;

  template <typename U> 
  struct rebind { typedef YaMemAlloc<U> other; };
};

int main(int argc, char** argv)
{
    A* pa1 = new A();
    delete pa1;

    A* pa2 = new(1) A();
    delete pa2;

    char* pc = new char[sizeof(A)];
    A* pa3 = new(pc) A();
    pa3->~A();

    delete pc;

    B* pb = new B();
    delete pb;

    std::vector<B, YaMemAlloc<B>> vecB;
    vecB.push_back(B());
    vecB.push_back(B());
    vecB.push_back(B());
    vecB.push_back(B());

    return 0;
}