Page 515 - Computer science 868 Class 12
P. 515

53             case 2:
                   54             n=ob.popvalue();

                   55             if(n==-9999)
                   56                System.out.println("Queue Underflow");

                   57             else
                   58               System.out.println(n+" deleted from queue");

                   59             break;
                   60             case 3:
                   61             ob.disp();

                   62             break;

                   63             default: System.out.println("Exit");
                   64          }
                   65              } while(ch>=1&&ch<=3);

                   66          }
                   67      }


                   Program 4     A linear data structure enables the user to add an address from rear end and remove address
                                 from front. Define a class Diary with the following details.               [ISC 2019]
                                 Class name               :   Diary
                                 Data Members/Instance variables
                                 Q[]                      :   an array to store the addresses
                                 size                     :   to store the maximum capacity of the array
                                 start                    :   to point to the index of the front end
                                 end                      :   to point to the index of the rear end
                                 Member Functions
                                 Diary(int max)           :    constructor to initialise the data members size = max, start = 0
                                                              and end = 0
                                 void pushadd(String n)    :   to add the address in the diary from the rear end if possible,
                                                              otherwise display the message “NO SPACE”
                                 String popadd()          :     to remove and return the address from the front end of the
                                                              diary if any, else returns “?????”
                                 void show ()             :   to display all the addresses in the diary
                                 Specify the class Diary giving details of the functions void pushadd(String) and String popadd()
                                 and void show().

                   1       import java.util.*;

                   2       class Diary
                   3       { String Q[];

                   4         int size,start,end;
                   5         Diary(int max)//constructor





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