MyAllocator.h

#ifndef MY_ALLOCATOR_H#define MY_ALLOCATOR_H#include
    
      //placement new#include
     
       //ptrdiff_t size_t//分配内存template
      
       inline T* _allocator(ptrdiff_t n,T*){	T* temp = (T*)(::operator new((size_t)(n*sizeof(T))));	if (temp == 0){		cout << "out of memory" << endl;		exit(1);	}	return temp;}//释放内存template
       
        inline void _deallocator(T* ptr){	::operator delete(ptr);}//构造对象template
        
         inline void _construct(T* ptr, const V& value){	new (ptr) T(value); //定位new，在指定地址处构造对象}//析构对象template
         
          inline void _destroy(T* ptr){ ptr->~T();}template
          
           class MyAllocator{public: //型别定义 typedef T value_type; typedef T* pointer; typedef const T* const_pointer; typedef T& reference; typedef const T& const_reference; typedef size_t size_type; typedef ptrdiff_t difference_type; template
           
             struct rebind{ typedef MyAllocator
             other; }; pointer allocator(size_type n){ return _allocator((difference_type)n,(pointer)0); } void deallocator(pointer ptr){ _deallocator(ptr); } void construct(pointer ptr, value_type value){ _construct(ptr, value); } void destroy(pointer ptr){ _destroy(ptr); } pointer address(reference x){ return (pointer)&x; } const_pointer address(reference x) const{ return (const_pointer)&x; } size_type max_type() const{ return size_type(UINT_MAX / sizeof(T)); }};#endif
           
          
         
        
       
      
     
    

main.cpp

#include "MyAllocator.h"#include
    
     using namespace std;int main(){	MyAllocator
     
       alloc;	int* ptr=alloc.allocator(2);	alloc.construct(ptr, 10);	alloc.construct(ptr+1, 8);	cout << *ptr << endl;	cout << ptr[1] << endl;	alloc.destroy(ptr);	alloc.destroy(ptr + 1);	alloc.deallocator(ptr);		MyAllocator
      
       ::rebind
       
        ::other dalloc;	double* p = dalloc.allocator(2);	dalloc.construct(p, 3.5);	cout << *p << endl;	dalloc.destroy(p);	dalloc.deallocator(p);	system("pause");	return 0;}