Сборна памет

 class A{

   public:

      static void *operator new(size_t size);

      static void operator delete(void *obj, size_t size);

      ...

   private:

      union {

            ARepresentation *prep;

            A *pnext;

      }

      static const int BLOCK_SIZE;

      static A *pFreeListHead;

};



void* A::new(size_t size){

      if(size !=sizeof(A))

             return ::operator new(size);

     A* p = pFreeListHead;

     if(p)

             pFreeListHead = pFreeListHead->pnext;

     else{

            A* pBlock = static_cast<A*>(::operator new(BLOCK_SIZE*sizeof(A)));

            for(int i = 1; i < BLOCK_SIZE-1; ++i){

                  pBlock.pnext = &pBlock[i+1];

            }

             pBlock[BLOCK_SIZE-1].pnext = NULL;

             p = pBlock;

             pFreeListHead = &pBlock[1];

     }

     return p;

}



void A::operator delete(void *obj, size_t size){

    if(!obj)

        return;

    A* p = static_cast<A*>(obj);

    p->pnext = pFreeListHead;

    pFreeListHead = p;

}