CPP - Constructor & Destructor

 

CPP

Constructor & Destructor

Fill in the blanks

1.   Creating on Object is called  Constructor

2.   Destructor means Deleting an object

3.   Write a Symbol of Destructor   ~     

4.   Class name same as function name is called  Constructor

5.   How many Constructor presents in CPP  5  

6.   Constructor with no parameter is called  Default Constructor

7.   Constructor with argument are called Parameterized Constructor

8.   Constructor with object reference as its argument is called Copy Constructor

9.   Write a symbol of Copy Constructor  &  

10.         Allocating memory while creating an objects is called Dynamic  Constructor

11.         Constructor overloading means function name same , argument different

 

Answer the following Question

                                                                              (4 marks)

1.Write Default constructor Program

class  student{

private:

      int rlno;

float mark;

public:

student(){}     /*default constructor*/

void get()

{

cout<<"get rlno and mark";

cin>>rlno>>mark;

}

void put()

{

cout<<"rlno="<<rlno;

cout<<"mark="<<mark;

}

};

void main()

{

student s;     /*calling default constructor*/

}

 

2.Write a Program for Destructor

#include<iostream.h>

#include<conio.h>

class student{

 private:

    int rlno;

    float mark;

 public: 

    student(){}

    student(int r,float m)

   {

     rlno=r;

     mark=m;

   }

   void put()

    {

      cout<<"Rlno="<<rlno<<endl;

      cout<<"Mark="<<mark;

     }

   ~student()

     {

      cout<<"destructor called";

   }

};

void main()

{

student k(120,78);

clrscr();

k.put();

getch();

}

3.Write a Program for Copy Constructor

#include<iostream.h>

#include<conio.h>

class student{

 private:

      int rlno;

      float mark;

 public:

       student(){}

       student(int r,float m)

      {

         rlno=r;

         mark=m;

         }

 student(student &t)

  {

      rlno=t.rlno;

      mark=t.mark;

   }

   void put()

   {

    cout<<"rlno="<<rlno<<endl;

    cout<<"mark="<<mark<<endl;

   }

};

void main()

{

student s;

student k(120,78);

student R(k);

clrscr();

R.put();

getch();

}

4. Write a  Program  for Parametrized  Constructor

#include<iostream.h>

#include<conio.h>

class student{

   private:

             int rlno;

             float mark;

public:

       student(){}  /* default constructor*/

       student(int r,float m) /*parameterized constructor*/

 {

       rlno=r;

       mark=m;

  }

  void put()

 {

cout<<"rlno="<<rlno<<endl;

cout<<"mark="<<mark;

}

};

void main()

{

student s;

student k(120,78);

clrscr();

k.put();

getch();

}

 

Answer the following Question

                                                                              (10 marks)

1.What is Constructor and Destructor?Write its types.Write a Program for Default Constructor, Parameterized Constructor, Copy Constructor, Constructor Overloding Program

 

Constructor

Creating an object is called Constructor

Destructor

Deleting an object is called Destructor

TYPES OF CONSTRUCTOR

·       default constructor

·       parameterized constructor

·       copy constructor

·       dynamic constructor

·       constructor over loading

 

Default and Parameterized Constructor

#include<iostream.h>

#include<conio.h>

class student{

   private:

             int rlno;

             float mark;

public:

       student(){}  /* default constructor*/

       student(int r,float m) /*parameterized constructor*/

 {

       rlno=r;

       mark=m;

  }

  void put()

 {

cout<<"rlno="<<rlno<<endl;

cout<<"mark="<<mark;

}

};

void main()

{

student s;

student k(120,78);

clrscr();

k.put();

getch();

}

 

Copy Constructor

#include<iostream.h>

#include<conio.h>

class student{

 private:

      int rlno;

      float mark;

 public:

       student(){}

       student(int r,float m)

      {

         rlno=r;

         mark=m;

         }

 student(student &t)

  {

      rlno=t.rlno;

      mark=t.mark;

   }

   void put()

   {

    cout<<"rlno="<<rlno<<endl;

    cout<<"mark="<<mark<<endl;

   }

};

void main()

{

student s;

student k(120,78);

student R(k);

clrscr();

R.put();

getch();

}

Constructor Overloading

#include<iostream.h>

#include<conio.h>

class student{

 private:

        int rlno;

        float mark;

 public:

        student(){}

        student(int r,float m)

       {

        rlno=r;

        mark=m;

        }

        void put()

        {

         cout<<"Rlno="<<rlno<<endl;

         cout<<"Mark="<<mark<<endl;

         }

};

void main()

{

student s;

student k(120,78);

clrscr();

k.put();

getch();

}