import java.util.Scanner;
public class Node
{
int info;
Node next,prev;
Node left,right;
}
public class DoubleLL
{
Node start=new Node();
Node end=new Node();
Node curr=new Node();
int num;
DoubleLL()
{
start=null;
end=null;
num=0;
}
void AddBeg(int val)
{
Node t=new Node();
t.info=val;
if(num++==0)
{
t.next=null;
t.prev=null;
end=t;
}
else
{
start.prev=t;
t.next=start;
}
start=t;
}
void AddEnd(int val)
{
Node t=new Node();
t.info=val;
if(num++==0)
{
t.next=null;
t.prev=null;
start=t;
}
else
{
end.next=t;
t.prev=end;
}
end=t;
}
void DelBeg()
{
if(num==0)
System.out.println("Linked List Empty");
else
{
if(start==end)
{
start=null;
end=null;
num=0;
}
else
{
start=start.next;
start.prev=null;
}
}
}
void DelEnd()
{
if(num==0)
System.out.println("Linked List Empty");
else
{
if(start==end)
{
start=null;
end=null;
num=0;
}
else
{
end=end.prev;
end.next=null;
}
}
}
void Search(int val)
{
Loop:
{
for(curr=start;curr!=null;curr=curr.next)
{
if(curr.info==val)
{
System.out.println("Element Found");
break Loop;
}
}
System.out.println("Element Not Found");
}
}
void Display()
{
curr=start;
System.out.print("Start -> ");
while(curr!=null)
{
System.out.print(curr.info + " -> ");
curr=curr.next;
}
System.out.println("End");
}
public static void main(String[] args)
{
int ch,val;
DoubleLL dl=new DoubleLL();
Scanner in = new Scanner(System.in);
while(true)
{
System.out.println("-----------------------------------");
System.out.println("Enter your Choice");
System.out.println("1 : Add Beg 2 : Add End 3 : Del Beg 4 : Del End 5 : Display 6 : Search 7 : Exit");
ch=in.nextInt();
switch(ch)
{
case 1:
{
System.out.print("Enter a Number = ");
val=in.nextInt();
dl.AddBeg(val);
break;
}
case 2:
{
System.out.print("Enter a Number = ");
val=in.nextInt();
dl.AddEnd(val);
break;
}
case 3:
{
dl.DelBeg();
break;
}
case 4:
{
dl.DelEnd();
break;
}
case 5:
{
dl.Display();
break;
}
case 6:
{
System.out.println("Enter Element to Search");
val=in.nextInt();
dl.Search(val);
break;
}
case 7:
System.exit(0);
break;
default : continue;
}
}
}
}