Question

Program Description: A bus has 28 seats, arranged in 7 rows and 4 columns: This seating arrangement is mapped, row-wise, to a 1D-array of size 28: 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 0 1 2 3 21 22 23 24 25 Implement a well-structured Java program to enable a user to make and cancel seat reservations for the bus. The program uses Array to store the reservation information: 0 indicates that a seat is not reserved, and 1 indicates that a seat is reserved. Originally all seats are not reserved: 0000 0000 0000 0000 0000 0000 0000 Your program starts by initializing a ID-array. It must then display the following menu: 1. Display number of available seats. 2. Display seat status for all seats. 3. Reserve seats). 4. Delete reservation(s). 5. Exit. Please select your choice:

Answer 1

Java code

import java.util.*;

class solution
{
   public static void main(String args[])
   {
       // create an array with size 28 to store bus seats status
       int seats[] = new int[28];
  
       int i=0;

       // initialize all 28 elements of array with 0
       while(i<28)
       {
           seats[i] = 0;
           i+=1;
       }

       // declare a variable to store available seats
       int seats_count = 28;

       // create object for scanner class
       Scanner scan = new Scanner(System.in);

       // iterate while loop until user chooses exit option
       while(true)
       {
           // print menu
           System.out.println("1.Display number of available seats.\n2.Display seat status for all seats.\n3.Reserve seat(s).\n4.Delete reservation(s).\n5.Exit\n");

           // ask user to chose an option
           System.out.print("Please select your choice[1, 2, 3, 4 or 5]: ");

           // read users option
           int option = scan.nextInt();

          
           // if user option is 1          
           if(option == 1)
           {
               // count available seats
               int count = 0;
               for(i=0;i<28;i++)
                   if(seats[i] == 0)
                       count++;

               // print available seats
               System.out.println("\nNumber of available seats = "+count);
           }

           // if user option is 2
           else if(option == 2)
           {
               // call displaySeats() method by passing seats array
               displaySeats(seats);
           }

           // if user option is 3
           else if(option == 3)
           {

               // call displaySeats() method by passing seats array
               displaySeats(seats);

               // display available seats
               System.out.print("\nThere are "+seats_count+" seats available. Please enter required number of seats: ");

               // read number of required seats to reserve
               int r_seats = scan.nextInt();
              
               // check for available seats
               if(r_seats > seats_count)
               {
                   // print insufficient available seats
                   System.out.println("\nError: Insufficient available seats.");
               }
               // check for required seats number validity
               else if(r_seats <= 0)
               {
                   // print invalid number of seats
                   System.out.println("\nError: Invalid number of seats.");
               }
               else
               {
                   // read each and every seat number and check if it is reserved
                   int flag = 0;
                   for(i=0;i<r_seats;i++)
                   {
                       System.out.print("Enter seat number to reserve: ");
                       int seat = scan.nextInt();
                       if(seats[seat-1] == 1)
                       {
                           flag = 1;
                           break;
                       }
                       else
                       {
                           seats[seat-1] = 1;
                           seats_count--;
                       }
                   }
                   // if any one of the seats is already empty, print error message
                   if(flag == 1)
                   {
                       System.out.println("Error: one or more required seats already reserved.");
                   }
                   else
                   {   // print success message
                       System.out.println("Required seats are successfully reserved.");
                   }
               }
              
           }

           // if user option is 4
           else if(option == 4)
           {
               // call displaySeats() method by passing seats array
               displaySeats(seats);

              
               System.out.print("\n Please enter required number of seats to be deleted: ");

               // read number of required seats to delete
               int r_seats = scan.nextInt();
              
               // check for seats numbers validity
               if(r_seats > seats_count || r_seats <= 0)
               {
                   System.out.println("\nError: Invalid number of reservations to delete.");
               }
               else
               {
                   // read each and every seat number and check if it is reserved
                   int flag = 0;
                   for(i=0;i<r_seats;i++)
                   {
                       System.out.print("Enter seat number of reservation to be deleted: ");
                       int seat = scan.nextInt();
                       if(seats[seat-1] != 1)
                       {
                           flag = 1;
                           break;
                       }
                       else
                       {
                           seats[seat-1] = 0;
                           seats_count++;
                       }
                   }
                   // if any one of the seats is already empty, print error message
                   if(flag == 1)
                   {
                       System.out.println("Error: one or more required seats already empty.");
                   }
                   else
                   {   // print success message
                       System.out.println("Required reservations successfully deleted.");
                   }
               }
           }
           else if(option == 5)
           {
               // stop the program
               break;
           }
           else
           {
               System.out.println("\nPlease chose a valid option");
           }
          
           // ask user to press enter key
           System.out.print("\nPress Enter key to continue . . .");
           String c = scan.nextLine();
           c = scan.nextLine();
           System.out.println("");
       }

   }
  
   public static void displaySeats(int seats[])
   {
       // visit each seat in the seats array
       System.out.println("");
       for(int i=0;i<7;i++)
       {

           for(int j=1;j<=4;j++)
           {
               if(seats[i*4+j-1] == 0)
                   // print seat number
                   System.out.print("[\t"+((i*4)+j)+"\t] ");
               else
                   // print reserved
                   System.out.print("\tReserved ");
           }
           System.out.println("");
       }
   }  
}

Sample Input/Output

rgukt-rkv@rguktrkv-TravelMate-P243-M:-/Documents/HomeworkLib/Dec 11$ java solution 1.Display number of available seats. 2.Display seat status for all seats. 3. Reserve seat(s). 4.Delete reservation(s). 5. Exit Please select your choice[1, 2, 3, 4 or 5]: 1 Number of available seats = 28 Press Enter key to continue... 1.Display number of available seats. 2.Display seat status for all seats. 3. Reserve seat(s). 4.Delete reservation(s). 5. Exit Please select your choice[1, 2, 3, 4 or 5]: 2 ] [ ][ ][ ][ ] [ ][ ][ ] [ لالالالالالالا 22 25 1 Press Enter key to continue...

rgukt-rkv@rguktrkv-TravelMate-P243-M: -/Documents/HomeworkLib/Dec 11 1.Display number of available seats. 2.Display seat status for all seats. 3. Reserve seat(s). 4.Delete reservation(s). 5. Exit Please select your choice[1, 2, 3, 4 or 5]: 3, ][ الالالالا w 29 28 There are 28 seats available. Please enter required number of seats: 4 Enter seat number to reserve: 1 Enter seat number to reserve: 10 Enter seat number to reserve: 19 Enter seat number to reserve: 25 Required seats are successfully reserved. Press Enter key to continue... 1.Display number of available seats. 2.Display seat status for all seats. 3. Reserve seat(s). 4.Delete reservation(s). 5. Exit Please select your choice[1, 2, 3, 4 or 5]: 2 Reserved [ PUUDU 13 Reserved [ 14 18 22 11 15 Reserved [ 23 ][ 21 Reserved [ 26 Press Enter key to continue...

rgukt-rkv@rguktrkv-TravelMate-P243-M: -/Documents/HomeworkLib/Dec 11 1.Display number of available seats. 2.Display seat status for all seats. 3. Reserve seat(s). 4.Delete reservation(s). 5. Exit Please select your choice[1, 2, 3, 4 or 5]: 3, Reserved [ [ 13 Reserved 14 18 11 15 Reserved [ 23 21 29 Reserved [ 26 27 28 There are 24 seats available. Please enter required number of seats: -1 Error: Invalid number of seats. Press Enter key to continue... 1.Display number of available seats. 2.Display seat status for all seats. 3. Reserve seat(s). 4.Delete reservation(s). 5. Exit Please select your choice[1, 2, 3, 4 or 5]: 4 Reserved [ 3 Reserved [ 14 7 11 15 Reserved 23 18 13 17 21 Reserved [ [ 22 26 27 Please enter required number of seats to be deleted: 1 Enter seat number of reservation to be deleted: 1 Required reservations successfully deleted. Press Enter key to continue...

1.Display number of available seats. 2.Display seat status for all seats. 3. Reserve seat(s). 4.Delete reservation(s). 5. Exit Please select your choice[1, 2, 3, 4 or 5]: 2 ][ il 3 7 Reserved [ 14 Reserved [ 21 18 22 23 Reserved [ Press Enter key to continue... 1.Display number of available seats. 2.Display seat status for all seats. 3. Reserve seat(s). 4.Delete reservation(s). 5. Exit Please select your choice[1, 2, 3, 4 or 5]: 6 Please chose a valid option Press Enter key to continue... 1.Display number of available seats. 2.Display seat status for all seats. 3. Reserve seat(s). 4.Delete reservation(s). 5. Exit Please select your choice[1, 2, 3, 4 or 5]: 5 rgukt-rkv@rguktrkv-TravelMate-P243-M:-/Documents/HomeworkLib/Dec 11$