Linked List

sid0812
Profile Answers by sid0812

Nov 11th, 2010

import java.io.*;

class node
{
  public int info;
  node next;
}

class link
{
  node head;
  public void initialize()
   {
   node head=null;
   }

  public void insert()throws Exception
   {
   int x;
   InputStreamReader ISR=new InputStreamReader(System.in);
   BufferedReader br=new BufferedReader(ISR);
   System.out.println("n enter element to be inserted");
   x=Integer.parseInt(br.readLine());
   node p=new node();
   p.info=x;
   p.next=null;

   if(head==null)
   {
   head=p;
   }

   else
   {
   node t;
   t=head;
   while(t.next!=null)
   {
   t=t.next;
   }
   t.next=p;
   }
   }

  public void delete()throws Exception
   {
   int y;
   if(head==null)
   {
   System.out.println("n empty tree");
   }

   else
   {
   System.out.println("n enter element to be deleted");
   InputStreamReader ISR=new InputStreamReader(System.in);
   BufferedReader br=new BufferedReader(ISR);
   y=Integer.parseInt(br.readLine());

   node t;
   node prev;
   t=head;
   prev=null;
   while(y!=t.info&&t.next!=null)
   {
   prev=t;
   t=t.next;
   }

   if(y==t.info)
   {
   if(t==head)
   {
   head=t.next;
   t.next=null;
   }
   else
   {
   prev.next=t.next;
   t.next=null;
   }
   }
   else
   {
   System.out.println("n not found");
   }

   }
   }

  public void traverse()
   {

   node t;
   if(head==null)
   {
   System.out.println("n empty tree");
   }
   else
   {
   t=head;
   while(t!=null)
   {
   System.out.println("n"+t.info);
   t=t.next;
   }
   }
   }
  }

class list
{
  public static void main(String args[]) throws Exception
   {
   link l=new link();
   l.initialize();

   int c;
   while(true)
   {
   System.out.println("n 1:insert");
   System.out.println("n 2:delete");
   System.out.println("n 3:traverse");
   InputStreamReader ISR=new InputStreamReader(System.in);
   BufferedReader br=new BufferedReader(ISR);
   c=Integer.parseInt(br.readLine());

   switch(c)
   {
   case 1:
   l.insert();
   break;

   case 2:
   l.delete();
   break;

   case 3:
   l.traverse();
   break;

   default: System.out.println("n wrong choice");


   }
   }

   }
  }