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package acm;


import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class ACM {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String a = br.readLine();
        String b = br.readLine();
        boolean res = call(a,b);
        if (res == true){
            System.out.println("YES");
        }else{
            System.out.println("NO");
        }
    }

    private static boolean call(String x, String y) {
        int Len1 = x.length()/2;
        int Len2 = y.length()/2;
        if (x.equals(y)){
            return true;
        }
        if(x.length() == 1){
            return false;
        }if(x.length() % 2 != 0){
            return false;
        }
        String s1 = x.substring(0, Len1);
        String s2 = x.substring(Len1);
        String t1 = y.substring(0, Len2);
        String t2 = y.substring(Len2);

        return (call(s1, t1) && call(s2, t2)) || (call(s1, t2) && call(s2, t1));
    }
}