判断串是否为回环变位串

import java.io.BufferedInputStream;
import java.util.Scanner;

public class test {
    public static void main(String[] args) {
        Scanner cin = new Scanner(new BufferedInputStream(System.in));
        String s = cin.next();
        String t = cin.next();
        cin.close(); // indexOf返回指定子字符串在此字符串中第一次出现处的索引,如果找不到子串就返回-1
        if ((s.length() == t.length()) && (s.concat(s).indexOf(t) >= 0)) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
}