Design and implement a counted_ptr that is a type that holds a pointer to an object of type T and a pointer to a “use count” (an int) shared by all counted pointers to the same object of type T. The use count should hold the number of counted pointers pointing to a given T. Let the counted_ptr’s constructor allocate a T object and a use count on the free store. Let counted_ptr’s constructor take an argument to be used as the initial value of the T elements. When the last counted_ptr for a T is destroyed, counted_ptr’s destructor should delete the T. Give the counted_ptr operations that allow us to use it as a pointer. This is an example of a “smart pointer” used to ensure that an object doesn’t get destroyed until after its last user has stopped using it. Write a set of test cases for counted_ptr using it as an argument in calls, container elements, etc.