// Ex: Think through how one could use the stack directly,
// instead of first removing non-letters. Why is it difficult?

import java.util.*;

public class Palindrome2 {

    public static void main (String[] argv)
    {
	// Oldest known recorded palindrome.
        String str = "Evil did I dwell; lewd I did live";
        System.out.println ( str + " " + checkPalindrome(str) );

	// Oldest reference.
        str = "Madam, I'm Adam";
        System.out.println ( str + " " + checkPalindrome(str) );

	// One of the most famous.
        str = "A man, a plan, a canal: Panama";
        System.out.println ( str + " " + checkPalindrome(str) );

	// Not a palindrome, but a palingram:
        str = "He was, was he?";
        System.out.println ( str + " " + checkPalindrome(str) );
    }
    

    static String checkPalindrome (String str)
    {
    }

}