Constructors

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                  Constructors 


Constructor is the process to use the class and function is being used in easy way.

Constructor

A constructor is used to initialize the data member of a class. There are three types of constructor:

  • Default constructor 
  • Parameterized constructor
  • Copy constructor

  • A constructor having zero arguments is called as default constructor.
  • A constructor that passes one or more number of arguments is called as parameterized constructor.

Example of constructor

class abc
{
private:
int x;
public:
   abc() //constructor defined
{
   x = 10; //private data member initialized
   cout<<x;
   }
};
void main()
{
abc ob; //constructor called
}

Output:
10

Example of parameterized constructor

class abc
{
private:
int x;
public:
abc(int x1)
{
   x=x1;
   cout<<x;
}
};
void main()
{
abc ob(10);
}

Output: 10.


This is how the use of constructor and that make program more easy to use.

Destructor


A destructor is used to destroy i.e. free up the memory space occupied by the objects of class.

Properties of Destructor
  1. Destructor has the same name as class name, but it is preceded by tilde (~) sign.
  2. Destructor releases the memory space occupied by the objects of a class, at the time of program termination.
  3. Destructor is called automatically, at the time of program termination.

Example of destructor

class abc
{
private:
int x;
public:
abc(int x1) //parameterized constructor
{
x = x1;
cout<<x;
}

~abc() // destructor
{
cout<<”\nDestructor called”;
}
};

void main()
{
abc ob(10); //parameterized constructor called- ob’s x will be set to 10
}// destructor called at program termination

Output:
10
Destructor called





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