c 2b 2b const shared ptr

1#include <memory>
2std::shared_ptr<int> foo = std::make_shared<int> (10);

1shared_ptr<T> p;             ---> T * p;                                    : nothing is const
2const shared_ptr<T> p;       ---> T * const p;                              : p is const
3shared_ptr<const T> p;       ---> const T * p;       <=> T const * p;       : *p is const
4const shared_ptr<const T> p; ---> const T * const p; <=> T const * const p; : p and *p are const.
5