题解 | #字符串反转#

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String str = scanner.nextLine();
        char[] chars = str.toCharArray();
        for (int i = 0; i < chars.length; i++) {
            if (chars[i] < 'a' || chars[i] > 'z') {
                return;
            }
        }
        StringBuffer sbu = new StringBuffer(str);
        StringBuffer s = sbu.reverse();
        System.out.println(s);
    }
}