跟上一道数组的是一样的,会用reverse就行

public class Main{
    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        
        while(scan.hasNext()){
            String str = scan.nextLine();
            StringBuilder strb = new StringBuilder();
            strb.append(str);
            strb.reverse();
            System.out.println(strb.toString());
        }
    }
}