[Java] 유효한 팰린드롬

팰린드롬: 앞에서 읽을때나 뒤에서 읽을 때나 같은 문자열

import java.util.Scanner;

public class Main {
    public String solution(String strings) {
        String answer = "NO";

        String s = strings.toUpperCase().replaceAll("[^A-Z]", "");
        String stringBuilder = new StringBuilder(s).reverse().toString();

        if (s.equals(stringBuilder)) {
            return "YES";
        }

        return answer;
    }

    public static void main(String[] args) {
        Main main = new Main();
        Scanner scanner = new Scanner(System.in);

        String str = scanner.nextLine();
        System.out.println(main.solution(str));
    }
}