int *pointer;

A():pointer(new int(1)) { std::cout << "构造" << pointer << std::endl; }

A(A& a):pointer(new int(*a.pointer)) { std::cout << "拷贝" << pointer << std::endl; } // 无意义的对象拷贝

A(A&& a):pointer(a.pointer) { a.pointer = nullptr;std::cout << "移动" << pointer << std::endl; }

~A(){ std::cout << "析构" << pointer << std::endl; delete pointer; }

A a,b;

if(test) return a;

else return b;

A obj = return_rvalue(false);

std::cout << "obj:" << std::endl;

std::cout << obj.pointer << std::endl;

std::cout << *obj.pointer << std::endl;

return 0;