import java.io.*;
import java.util.*;
class shop
{
    DataInputStream ds = new DataInputStream(System.in);
 
    void append(Vector v1) throws IOException
    {
            System.out.println("Enter the element to be Appended");
            System.out.println("Current capacity :"+ v1.capacity());
            v1.insertElementAt(ds.readLine(),v1.capacity());
            System.out.println("Append Successfully");
 
    }
    void insert(Vector v1) throws IOException
    {
        System.out.println("Enter the position to be inserted");
        Integer x2 = new Integer(ds.readLine());
        Integer pos = x2.intValue();
        System.out.println("Enter the element");
        v1.insertElementAt(ds.readLine(), pos);
            System.out.println("Inserted Successfully");
    }
    void delete(Vector v1) throws IOException
    {
    System.out.println("Enter the position to be deleted");
        Integer x1 = new Integer(ds.readLine());
        Integer pos = x1.intValue();
        v1.removeElementAt(pos);
        System.out.println("Deleted Successfully");
 
    }
    void display(Vector v1) throws IOException
    {
    int i=0;
    Enumeration vEnum = v1.elements();
    System.out.println("\t\t\t Shopping List");
    System.out.println("-----------------------");
    System.out.println("Items in Vector");
    System.out.println("Position          Item");
    while(vEnum.hasMoreElements())
    {
        System.out.println(i+"\t\t" +vEnum.nextElement());
        i++;
 
    }
 
 
 
    }
 
 
}
class shoppinglist {
    public static void main(String arg[]) throws IOException
    {
        Vector v = new Vector(5,10);
        shop ob = new shop();
        DataInputStream ds = new DataInputStream(System.in);
        for (int i=0; i<arg.length; i++)
        {
            v.addElement(arg[i]);
        }
        ob.display(v);
        while(true)
        {
            System.out.println("\t\t\t Shopping List");
            System.out.println("\t\t\t ----------------");
            System.out.println("1. Append");
            System.out.println("2. Delete");
            System.out.println("3. Insert");
            System.out.println("4. Display");
            System.out.println("5. Exit';");
            System.out.println("Enter ur choice");
            int ch = Integer.parseInt(ds.readLine());
            switch(ch)
            {
                case 1: ob.append(v);
                break;
                case 2: ob.delete(v);
                break;
                case 3: ob.insert(v);
                break;
                case 4: ob.display(v);
                break;
                case 5: System.exit(0);
                break;
                default: System.out.println("Enter correct choice");
                break;
            }
            }
 
        }
 
    }