1) What is the output of the following program? What if we add virtual to the destructors? #include <iostream> using namespace std;

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1 1) What is the output of the following program? What if we add virtual to the destructors? class Base Base() cout << "A" << endl; ~Base() cout << "B" << endl; ; class Derived : public Base Derived() cout << "C" << endl; ~Derived() cout << "D" << endl; ; Base *ptr = new Derived(); delete ptr;

2 2) What will the following program display? class Person virtual void eat() cout << "Yummy" << endl; virtual void speak() cout << "Hello" << endl; virtual void sleep() cout << "ZZZZ" << endl; ; class Student : public Person void speak() cout << "I love school" << endl; void study() cout << "Studying for Midterm test" << endl; void getreadyfortest () study(); sleep(); ; class ElCaminoStudent : public Student void speak() cout << "Go Warriors!" << endl; void sleep() cout << "ZZZ... CS2...ZZZZ" << endl; void getreadyforcs2test() study(); eat(); sleep(); ; int main( ) Person* array[3]; array[0] = new Person(); array[1] = new Student(); array[2] = new ElCaminoStudent; for (int i=0; i < 3; i++) array[i]->eat(); array[i]->speak(); array[i]->sleep();

3 Student * sp = new Student(); ElCaminoStudent *ecp = new ElCaminoStudent; sp->getreadyfortest(); ecp->getreadyforcs2test();

4 3) What is the output of the following code? class Base void output(int n) cout << "Hello Base" << n << endl; ; class Derived : public Base // This hides the output(int n) member function // from Base class void output() cout << "Hello Derived Class!" << endl; ; Base b; b.output(1); Derived d; d.output(); d.base::output(2);

5 4) What is the output of the following code? What if you make A::output( ) virtual? What if B::output( ) is virtual? What if both are virtual? class A void output() cout << "A" << endl; ; class B : public A void output() cout << "B" << endl; ; A *a = new A(); A *b = new B(); delete a, b; a->output(); b->output();

6 5) What is the output of the following code? class Person void Play() cout << "Person::Play" << endl; ; void Study() cout << "Person::Study" << endl; ; class Student: public Person virtual void Study() cout << "Student::Study" << endl; ; class CS_Student : public Student void Play() cout << "CS_Student::Play!" <<endl; void Study() cout << "CS_Student::Study!" << endl; ; void activity( Person &s ) s.play(); s.study(); CS_Student cs_student; activity(cs_student);

7 6) What is the output of the following code? class Person void Play() cout << "Person::Play" << endl; ; void Study() cout << "Person::Study" << endl; ; class Student: public Person virtual void Study() cout << "Student::Study" << endl; ; class CS_Student : public Student void Play() cout << "CS_Student::Play!" <<endl; void Study() cout << "CS_Student::Study!" << endl; ; void activity( Student &s ) s.play(); s.study(); CS_Student cs_student; activity(cs_student); Play around with putting the virtual keyword in different places, see what happens to this example and the previous one.

8 7) What is the output of the following code? class Other Other(int n) cout << "Other::" << n + 10 << endl; ~Other() cout << "~Other::-15" << endl; ; class Base int value; Base(int n): value(n) cout << "Base::" << n << endl; ~Base() cout << "~Base::" << -value << endl; ; class D1 : public Base Other o; D1(int n):base(n),o(n) cout << "D1::" << n + 5 << endl; ~D1() cout << "~D1::-10" << endl; ; D1 d(5);

9 8) What is the output of the following code? class Person Person(const char* name) : m_name(name) cout << m_name << endl; ~Person() cout << "~" << m_name << endl; private: const char* m_name; ; void funcb() cout << "1" << endl; Person x("x"); Person y("y"); throw 2; cout << "2" << endl; return; void funca() cout << "3" << endl; try funcb(); catch (int) cout << "4" << endl; cout << "5" << endl; try funca(); catch (int) cout << "6" << endl; catch (...) cout << "7" << endl; cout << "8" << endl; return 0;

10 9) What is the output of the following code? class Person Person(const char* name) : m_name(name) cout << m_name << endl; ~Person() cout << "~" << m_name << endl; throw -1; private: const char* m_name; ; void funcb() cout << "1" << endl; Person x("x"); Person y("y"); cout << "2" << endl; return; try funca(); catch (int) cout << "6" << endl; catch (...) cout << "7" << endl; cout << "8" << endl; return 0; void funca() cout << "3" << endl; try funcb(); catch (int) cout << "4" << endl; cout << "5" << endl;

11 10) What is the output of the following code? class Person Person(const char* name) : m_name(name) cout << m_name << endl; throw -1; ~Person() cout << "~" << m_name << endl; private: const char* m_name; ; void funcb() cout << "1" << endl; throw Person("X"); cout << "2" << endl; return; try funca(); catch (int) cout << "6" << endl; catch (...) cout << "7" << endl; cout << "8" << endl; return 0; void funca() cout << "3" << endl; try funcb(); catch (int) cout << "4" << endl; cout << "5" << endl;