monorail problem in java

import java.util.ArrayList;

import java.util.Scanner;

class assg05

{

      private static final Scanner in = new Scanner(System.in);

     

      public static void main(String s[])

      {

             ArrayList<Train> train = new ArrayList<Train>();

             ArrayList<Monorail> mono = new ArrayList<Monorail>();

           

             while(true)

             {

                   System.out.println("\n\n1. Add a train\n2. Add sequential stoppages\n3. Print train stoppages\n4.Add Mono rail\n5.Print Capacity");

                   System.out.print("Enter your choice: ");

                   int choice = in.nextInt();

                   in.nextLine();

                   switch(choice)

                   {

                         case 1: train.add(new Train());

                         break;

                         case 2: System.out.print("Enter the tain no: ");

                                 int nos = in.nextInt();

                                 in.nextLine();

                                 boolean flag = false;

                                 for(int i=0; i<train.size(); ++i)

                                 {

                                    flag = false;

                                    if(train.get(i).trainNo == nos)

                                    {

                                       train.get(i).addStop();

                                       flag = true;

                                       break;

                                    }  

                                 }

                               

                                 if(flag == false)

                                   System.out.println("Train Number not found");    

                         break;

                         case 3: System.out.print("Enter the tain no: ");

                                 int no = in.nextInt();

                                 in.nextLine();

                                 boolean flag1 = false;

                                 for(int i=0; i<train.size(); ++i)

                                 {

                                    flag1 = true;

                                    if(train.get(i).trainNo == no)

                                    {

                                       train.get(i).printStops();

                                       flag = true;

                                       break;

                                    }  

                                 }

                               

                                 if(flag1 == false)

                                   System.out.println("Train Number not found");

                         break;

                         case 4: mono.add(new Monorail());

                         break;

                         case 5: System.out.print("Enter the tain no: ");

                                 int no1 = in.nextInt();

                                 in.nextLine();

                                 boolean flag2 = false;

                                 for(int i=0; i<mono.size(); ++i)

                                 {

                                    flag1 = true;

                                    if(mono.get(i).trainNo == no1)

                                    {

                                       mono.get(i).printSeatCapacity();

                                       flag2 = true;

                                       break;

                                    }  

                                 }

                               

                                 if(flag2 == false)

                                   System.out.println("Train Number not found");

                         break;

                         case 6: System.exit(0);

                         default:System.out.println("Wrong choice entered");

                   }

             }

      }                

     

}

class Train

{

       private Scanner in = new Scanner(System.in);

       public static int n;

       public String source,destination;

       public int start,reach,totSeat,trainNo, noStop;

       public String stopArrival[][];

         

       Train()

       {

           

            System.out.print("Enter the source of train: ");

            source = in.nextLine();

            System.out.print("Enter the destination of train: ");

            destination = in.nextLine();

            System.out.print("Enter Start time: ");

            start = in.nextInt();

            System.out.print("Enter End time: ");

            reach = in.nextInt();

            System.out.print("Enter total no of seats: ");

            totSeat = in.nextInt();

            in.nextLine();

           

            ++n;

            trainNo = n;

            System.out.print("Train No: "+trainNo+"\n");

           

       }          

           

     

       public void addStop()

       {

              System.out.print("Enter the no. of stoppages:");

              noStop = in.nextInt();

           

              in.nextLine();

              stopArrival = new String[noStop][2];

             

              for(int i = 0; i<noStop; ++i)

              {

                  System.out.print("Enter the stopppage name: ");

                  stopArrival[i][0] = in.nextLine();

                  System.out.print("Enter the arrival time: ");

                  stopArrival[i][1] = in.nextLine();

              }  

                 

       }

     

       public void printStops()

       {

             System.out.printf("%-15s%15s%n","Stoppage Name","Arrival Time");

             System.out.println("-----------------------------------------");

             for(int i =0; i<noStop; ++i)

             {

                System.out.printf("%-15s%15s%n",stopArrival[i][0],stopArrival[i][1]);

             }

             System.out.println("-----------------------------------------");

       }

}

class Monorail extends Train

{

      private final Scanner in = new Scanner(System.in);

      String modelName;

      int ecoNo;

      int busNo;

     

      Monorail()

      {

          System.out.print("Enter the model name: ");

          modelName = in.nextLine();

          System.out.print("Enter seats no in economy class: ");                

          ecoNo = in.nextInt();

          System.out.print("Enter seats no in economy class: ");                

          busNo = in.nextInt();

         

          in.nextLine();

     }

   

     public void printSeatCapacity()

     {

         System.out.println("Model name: "+modelName);

         System.out.println("Seat Capacity: "+(ecoNo+busNo));

         System.out.println("Train no: "+ trainNo);

     }  

}          

           

           

           

           

           

           

           

           

           

/*

 * To change this license header, choose License Headers in Project Properties.

 * To change this template file, choose Tools | Templates

 * and open the template in the editor.

 */

package powerset;

import java.util.Scanner;

/**

 *

 * @author Vinayak

 */

public class Powerset {

    /**

     * @param args the command line arguments

     */

    public static void main(String[] args) {

        // TODO code application logic here

        Scanner in=new Scanner(System.in);

        System.out.println("enter the no of elements");

        int n=in.nextInt();

        int[] x=new int[n];

        for(int i=0;i<n;i++)

        {

            System.out.println("enter the number");

            x[i]=in.nextInt();

        }

       

       

       

    }

   

}