Problem 23
What is the purpose of a copy constructor?
Problem 24
Name two situations in which a copy constructor executes.
Problem 25
Name three things that you should do for classes with pointer member variables.
Problem 26
Suppose that you have the following classes, classA and classB: class classA { public: virtual void print() const; void doubleNum(); classA(int a = 0); private: int x; }; void classA::print() const { cout << "ClassA x: " << x << endl; } void classA::doubleNum() { x = 2 * x; } classA::classA(int a) { x = a; } class classB: public classA { public: void print() const; void doubleNum(); classB(int a = 0, int b = 0); private: int y; }; void classB::print() const { classA::print(); cout << "ClassB y: " << y << endl; } void classB::doubleNum() { classA::doubleNum(); y = 2 * y; } classB::classB(int a, int b) : classA(a) { y = b; } What is the output of the following function main? int main() { classA *ptrA; classA objectA(2); classB objectB(3, 5); Exercises | 855 ptrA = &objectA ptrA->doubleNum(); ptrA->print(); cout << endl; ptrA = &objectB ptrA->doubleNum(); ptrA->print(); cout << endl; return 0; }
Problem 29
Is it legal to have an abstract class with all member functions pure virtual?
Problem 30
Consider the following definition of the class studentType: public studentType: public personType { public: void print(); void calculateGPA(); void setID(long id); void setCourses(const string c[], int noOfC); void setGrades(const char cG[], int noOfC); void getID(); void getCourses(string c[], int noOfC); void getGrades(char cG[], int noOfC); void studentType(string fName = "", string lastName = "", long id, string c[] = NULL, char cG[] = NULL, int noOfC = 0); private: long studentId; string courses[6]; char coursesGrade[6] int noOfCourses; } Rewrite the definition of the class studentType so that the functions print and calculateGPA are pure virtual functions.
