Palindrome.java


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import java.lang.*;
import java.util.*;

class Palindrome {
	public static boolean isPalindrome(String s) {
		s = s.toLowerCase();
		char[] nonAlpha = s.toCharArray();
		ArrayList<Character> alpha = new ArrayList<Character>();
		for (char c : nonAlpha) {
		   if (Character.isLetter(c))
			   alpha.add(c);
		}

		int i = 0;
		int j = alpha.size() - 1;
		while (i < j) {
			if (alpha.get(i) != alpha.get(j))
				return false;
			i++;
			j--;
		}

		return true;
	}

	public static void main(String[] args) {
		String s = "A man, a plan, a canal: Panama";
		System.out.println(isPalindrome(s));
	}
}