#include #define DEBUG using namespace std; template class Smart_pointer{ T * pointer; unsigned * quantity; public: #ifdef DEBUG int number_of_copy(){ if(quantity) return *quantity-1; else return 0; } #endif //constructors and destructors Smart_pointer(): pointer(nullptr),quantity(nullptr){} Smart_pointer(T * p); Smart_pointer(T val); Smart_pointer(const Smart_pointer& sp); Smart_pointer operator=(const Smart_pointer& sp); ~Smart_pointer(); //other operators inline T& operator*(){return *pointer;} inline T* operator->(){return pointer;} }; int main() { Smart_pointer sp(5); cout<<"Test of the smart pointer."< s=sp; cout< Smart_pointer::Smart_pointer(T * p):pointer(p),quantity(new unsigned(1)){ if(!quantity && p){ delete p; p = nullptr; } } template Smart_pointer::Smart_pointer(T val):pointer(new T(val)){ if(pointer){ quantity = new unsigned(1); if(!quantity){ delete pointer; pointer = nullptr; } } } template Smart_pointer::Smart_pointer(const Smart_pointer& sp):pointer(sp.pointer),quantity(sp.quantity){ if(quantity) ++*quantity; } template Smart_pointer Smart_pointer::operator=(const Smart_pointer& sp){ if(pointer && pointer!=sp.pointer){ --(*quantity); if(!(*quantity)){ delete pointer; delete quantity; } } pointer = sp.pointer; quantity = sp.quantity; if(quantity) ++(*quantity); } template Smart_pointer::~Smart_pointer(){ if(pointer){ --(*quantity); if(!(*quantity)){ delete pointer; delete quantity; } } }

Smart pointers