Java program to demonstrate Linkedlist.

import java.io.*;
class lists
{
    int data;
    lists next;
}
class slist
{
    lists head,last,new1,temp;
    slist()
    {
        head=null;
    }
    public void create(int x)
    {
        new1=new lists();
        if(new1==null)
        {
            System.out.println("creation is not poosible");
            return;
        }
        new1.data=x;
        if(head==null)
        {
            head=last=new1;
            last.next=null;
        }
        else
        {
            last.next=new1;
            last=new1;
            last.next=null;
        }
    }
   

    public void display()
    {
        if(head==null)
        {
            System.out.println("Empty list");
            return;
        }
        System.out.println("The Elements are:");
        for(temp=head;temp!=null;temp=temp.next)
        {
            System.out.print(temp.data+"\t");
        }
        System.out.println();
    }
   


public void insert(int x,int d)
    {
        int pos,i;
        pos=x;
        new1=new lists();
        if(new1==null)
        {
            System.out.println("Insufficient Memory");
            return;
        }
        new1.data=d;
        if(head==null && pos==1)
        {
            head=last=new1;
            new1.next=null;
        }
        else if(head!=null && pos==1)
        {
            new1.next=head;
            head=new1;
        }
        else
        {
            i=2;
            temp=head;
            while(i<pos)
            {
                temp=temp.next;
                i++;
            }
            if(temp==null)
            {
                last.next=new1;
                last=new1;
                last.next=null;
            }
            else
            {
                new1.next=temp.next;
                temp.next=new1;
            }
        }
    }
    public void deletes(int p)
    {
        int pos,i;
        lists curr;
        pos=p;
        if(head==null)
        {
            System.out.println("Empty Linked List");
            return;
        }
        if(pos==1)
        {
            temp=head;
            head=head.next;
            temp=null;
        }
        else
        {
            i=2;
            temp=head;
            curr=temp.next;
            while(i<pos)
            {
                temp=temp.next;
                curr=temp.next;
                i++;
            }
            temp.next=curr.next;
            curr=null;
        }
    }
}
class linklist
{
    public static void main(String []args) throws IOException
    {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        slist sl=new slist();
        int opt,y,z;
        while(true)
        {
            System.out.println("1.creation");
            System.out.println("2.Insertion");
            System.out.println("3.Deletion");
            System.out.println("4.display");
            System.out.println("5.exit");
            System.out.println("enter ur choice:");
            opt=Integer.parseInt(br.readLine());
            switch(opt)
            {
                case 1:     System.out.println("Enter the number:");
                    y=Integer.parseInt(br.readLine());
                    sl.create(y);
                    break;
                case 2:     System.out.println("Enter the position:");
                    y=Integer.parseInt(br.readLine());
                    System.out.println("Enter the Data:");
                    z=Integer.parseInt(br.readLine());
                    sl.insert(y,z);
                    break;
                case 3:     System.out.println("Enter the position:");
                    y=Integer.parseInt(br.readLine());
                    sl.deletes(y);
                    break;
                case 4:     sl.display();
                    break;
                case 5:     System.exit(0);
            }
        }
    }
}