#include #include using namespace std; class test { string m_name; public: test(string name) : m_name(name){} void display() { cout << "How are you, " << m_name << "?\n"; } ~test() { cout << "Bye bye " << m_name << "\n"; } }; int main() { unique_ptr up1 = make_unique("Ketan"); up1->display(); shared_ptr sp1 = make_shared("Lalcheta"); shared_ptr sp2(sp1); cout << "Count of sp1 : " << sp1.use_count() << endl; cout << "Count of sp2 : " << sp2.use_count() << endl; sp2.reset(); cout << "sp2 reset \n"; cout << "Count of sp1 : " << sp1.use_count() << endl; cout << "Count of sp2 : " << sp2.use_count() << endl; //as sp2 is reset, below will crash //sp2->display(); sp1->display(); sp2 = sp1; cout << "sp2 reassigned \n"; cout << "Count of sp1 : " << sp1.use_count() << endl; cout << "Count of sp2 : " << sp2.use_count() << endl; shared_ptr sp3 = make_shared("A"); cout << "Count of sp3 : " << sp3.use_count() << endl; weak_ptr wp1 = sp3 ; cout << "\n\nweak pointer from sp3\n"; cout << "Count of sp3 : " << sp3.use_count() << endl; cout << "Locking weak_ptr of sp3\n" ; (wp1.lock())->display(); //below would not increase count //shared_ptr a = wp1.lock(); cout << "Count of sp3 : " << sp3.use_count() << endl; cout << "Is wp expired or not " << wp1.expired() << "\n"; cout << "Reset sp3\n"; sp3.reset(); cout << "Is wp expired or not " << wp1.expired() << "\n"; //below would crash //(wp1.lock())->display(); return 0; }

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