CheckPalindrome.java

import java.util.*;

public class CheckPalindrome {

	public static void main(String[] args) {
		MyList<Integer> l1 = new MyList<Integer>(new Integer[] {1,2,3,4,3,2,1});
		MyList<Integer> l2 = new MyList<Integer>(new Integer[] {1,2,2});
        
		l1.print();
		System.out.println("Is list palindrome: " + isPalindrome(l1));
		
		System.out.println();
		
		l2.print();
		System.out.println("Is list palindrome: " + isPalindrome(l2));
		
	}
	
	/**
	 * use a stack to check palindrome
	 * @param list
	 * @return true if list is palindrome
	 */
	public static boolean isPalindrome(MyList<Integer> list){
		Stack<Integer> s = new Stack<Integer>();
		Node<Integer> curr = list.head;
		//store value into stack
		while(curr != null){
			s.push(curr.val);
			curr = curr.next;
		}
		
		//pop from stack and compare to the list
		curr = list.head;
		while(!s.isEmpty()){
			if(s.pop() != curr.val){
				return false;
			}
			curr = curr.next;
		}
		
		return true;
		
	}

}