Page 236 - Cs_withBlue_J_C11_Flipbook
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A constructor is a member function that has the same name as that of a class and is used to initialise the instance
              variables of the objects that are created.
              Syntax:

                  class [name_of_class]
                  {
                      //data members
                      // A constructor
                      [name_of_class]()
                      {
                          //Statements;
                      }
                      //methods
                  }
              Let us see the following programs.

                Program 6     Define a class named ParkingLot with the following description:
                              Instance variables/Data members
                              String vno        :    To store the vehicle number
                              int hours         :    To store the number of hours the vehicle is parked in the parking lot
                              double bill       :   To store the bill amount
                              Member Methods
                              ParkingLot()      :    Non-parameterised Constructor
                              void input( )     :    To input and store the vno and hours
                              void calculate( )   :      To compute the parking charge at the rate of `3 for the first hours or
                                                    part thereof, and `1.50 for each additional hour or part thereof.
                              void display ( )    :    To display the detail
                              Write a main method to create an object of the class and call the above methods.

                1       import java.util.*;
                2       class ParkingLot {
                3           String vno;

                4           int hours;

                5           double bill;
                6           PartkingLot()
                7           {

                8                 hours=0;
                9                 bill=0.0;

                10           }
                11           void input()

                12          {
                13              Scanner sc = new Scanner(System.in);

                14              System.out.print("Enter vehicle number: ");
                15              vno = sc.next();

                16              System.out.print("Enter hours: ");


                234234  Touchpad Computer Science-XI
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