验证回文串(aa)

题目

import java.util.Deque;
import java.util.LinkedList;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		char[] c = s.toCharArray();
		Deque<Character> dq = new LinkedList<>();
		for(char ch:c) {
			dq.add(ch);
		}
		while(!dq.isEmpty()) {
			if(dq.size() == 1) {
				System.out.println("Y");
				return ;
			}
			//aa
			if(dq.getFirst() == dq.getLast()) {
				dq.removeFirst();
				dq.removeLast();
			}else {
				System.out.println("N");
				return ;
			}
//			if(dq.getFirst()!=dq.getLast()) {
//				System.out.println("N");
//				return ;
//			}
		}
		System.out.println("Y");
		sc.close();
	}
}

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		char[] s = sc.next().toCharArray();
		int l = 0;
		int r = s.length-1;
		while(l<r) {
			if(s[l]!=s[r]) {
				System.out.println("N");
				return ;
			}
			l++;
			r--;
		}
		System.out.println("Y");
 		sc.close();
	}
}