import java.util.Scanner;
import java.util.Arrays;
public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String a = sc.next();
    String b = sc.next();
    char[] aa = new char[a.length()];
    char[] bb = new char[b.length()];

    for(int i = 0; i<a.length(); i++) {
      aa[i] = a.charAt(i);
      bb[i] = b.charAt(i);
     }

     Arrays.sort(aa);
     Arrays.sort(bb);

    if(Arrays.equals(aa, bb)){
      System.out.println("YES");
    }else{
      System.out.println("NO");
    }
  }
}