How to check a Linked-List is a Palindrome.

Solution Approach:

First thing is we should know about palindrome.

What is Palindrome?
The list must be the same backwards and forwards such as

0-> 1 -> 2->1->0 This leads us to our first solution.

This problem can solved in many ways,

1. Reverse and Compare
2. Iterative Approach
3. Recursive Approach

Among three i will first solve this problem using Iterative Approach just see the below 

Implementation:

public boolean isPalindrome(LinkedListNode head)

{

LinkedListNode fast =head;

LinkedListNode slow =head;

Stack<Interger> stack=new Stack<Interger>();

while(fast!=null && fast.next !=null)

{

 stack.push(slow.data);

 slow=slow.next;

 fast=fast.next.next;

 

}

if(fast!=null)

{

  slow =slow.next;

}

while(slow!=null)

{

int top=stack.pop().intValue();

if(top!=slow.data)

                {

   return false;

}

slow=slow.next;

}

return true;

}

Now you can try others too......