}
~Vector(){
if (value!=NULL)
delete value;
}
};
void main()
{
Vector v(5);
v.showdata();
Vector v2(v);
v2.showdata();
}
a. Explain why the program incurs one memory error at run-time.
b. Now add the following code segment in the Vector class definition.
Vector(const Vector&v){
dimension = v.dimension;
value=new int[dimension];
for (int i=0; i<dimension; i++)
value[i]=v.value[i];
}
Check if the program still incurs the memory error or not. Explain why.
2.3) a. Test the following program in a Visual C++ environment:
class some{ // code segment a
public:
~some() {
cout<<"some's destructor"<<endl;
}
};
void main() {
some s;
s.~some();
}
What is the output of the above program during execution? Explain the output.
b. Test the following program in Visual C++ environment:
class some{ // code segment b
int *ptr;
public:
some(){
ptr= new int;
}
~some(){
cout<<"some's destructor"<<endl;
if (ptr!=NULL){
cout<<"delete heap memory"<<endl;
delete ptr;
}
}
};
void main()
{
some s;
// s.~some();
}
What is the output of the above program during execution? Explain the output.
c. In the main() function of the program in b, if we remove the two slashes (//) before the statement s.~some(); then what the result is when the program is executed ? Explain why.
2.4) Given the class definition as follows:
class Auto {
public:
Auto(char*, double);
displayAuto(char*, double);
private:
char* szCarMake;
double dCarEngine;
};
Auto::Auto(char* szMake, double dEngine){
szCarMake = new char[25];
strcpy(szCarMake, szMake);
dCarEngineSize = dCarEngine;
}
Auto::displayAuto(){
cout<<“The car make: “<<szCarMake<<endl;
cout<<“The car engine size: “<<dCarEngine<<endl;
}
void main(){
Auto oldCar(“Chevy”, 351);
Auto newCar(oldCar);
oldCar.displayAuto();
newCar.displayAuto();
}
- Add an appropriate copy constructor to the Auto class .
- Add an appropriate destructor to the Auto class .
c. Run all the modifications in a C++ environment.
Lab session 10: inheritance
1. objective
The objectives of Lab session 10 are (1) to get familiar with class inheritance; (2) to learn the workings of the constructor and destructor of a derived class.
This lab session will use the inheritance hierarchies in the following figure.
2. experiment
2.1) Given the Point class defined as follows.
class Point{
private:
int color;
protected:
double x;
double y;
public:
Point(double x=0, double y=0){
this->x=x; this->y=y;
}
void move(double dx, double dy){
x=x+dx;
y=y+dy;
}
~Point(){
cout<<"Destructor Point called";
}
};
Derive from the class Point, another class named Point_Derive1 class, which is defined as follows.
class Point_Derive1:public Point{
private:
double z;
public:
Point_Derive1();
void move(double dx, double dy, double dz);
~Point_Derive1();
};
a. List out the data members and member functions of the Point_Derive1 class. And determine the access specifier of each of these members.
Derive from the class Point, another class named Point_Derive2 class, which is defined as follows.
class Point_Derive2:protected Point{
private:
double z;
public:
Point_Derive1();
void move(double dx, double dy, double dz);
~Point_Derive1();
};
b. List out the data members and member functions of the Point_Derive2 class. And determine the access specifier of each of these members.