COMPUTER SCIENCE CONSTRUCTORS AND DESTRUCTORS

DELHI 2004:

2.a)Given the following C++ code, answer thequestions (i)and(ii)

class TestMeOut
{ public:
~TestMeOut( ) //Function 1
{
cout<<”Leaving the examination hall”<<endl;
}
TestMeOut( ) //Function 2
{
cout<<”Appearing for examination”<<endl;
}
void MyWork( )
{
cout<<”Attempting Questions”<<endl;
}
};

(i) In Object Oriented programming,what is Function 1 referred as and when does it get invoked/called?

Ans: Function 1 is called as Destructor, It will automatically executed at the time of destruction of the object of class TestMeOut.

(ii) In Object Oriented Programming,what is Function 2 referred as and when does it get invoked/called?

Ans: Function 2 is called as constructor(Non-parameterized or default constructor) , it will automatically executed at the time of creation of the object of class TestMeOut.

DELHI 2003:

2.b) Define a class Play in C++ with thefollowing specifications:

Private members of class Play

  • Play code      integer
  • Playtime        25 character
  • Duration        float
  • Noofscenes integer

Public member function of class Play

  • A constructer function to initialize Duration as 45 and Noofscenes as
  • Newplay() function to values for Playcode and Playtitle.
  • Moreinfor() to assign the values of assign the values of Duration and Noofscenes with the of corresponding values passed as parameters to this function.
  • Shoplay() function to display all the dataq members on the screen.

Ans:

#include<iostream.h>
#include<conio.h>
#include<string.h>
#include<stdio.h>
class Play
{ int Playcode;
char Playtitle[25];
float Duration;
int Noofscenes;
public:
Play( )
{ Duration=45;
Noofscenes=5;
}
void Newplay( )
{ cout<<"\nEnter the Play Code: ";
cin>>Playcode;
cout<<"\nEnter the Play Title: ";
gets(Playtitle);
}
void Moreinfor(float D,int N)
{ Duration = D;
Noofscenes = N;
}
void Showplay( )
{ cout<<"\nThe Play Code : “<<Playcode;
cout<<"\nThe Play Title : “ <<Playtitle;
cout<<"\nThe Duration :” <<Duration;
cout<<"\nThe No ofScenes:"<<Noofscenes;
}
};
void main( )
{ clrscr( );
Play P;
P.Newplay( );
float Dur;
int NS;
cout<<"\nEnter the Duration andNumber of Scenes: ";
cin>>Dur>>NS;
P.Moreinfor(Dur,NS);
P.Showplay( );
getch( );
}

 

CBSE Computer Science Solved Revision Tour By Mr. Ravi Kiran ( [email protected] )