import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String A = sc.next();
    String B = sc.next();
    String ans = "YES";
    for(char c = 'a'; c <= 'z'; c++) {
      int na = 0;
      int nb = 0;
      for(int i = 0; i < A.length(); i++) {
        if(A.charAt(i) == c) na++;
        if(B.charAt(i) == c) nb++;
      }
      if(na != nb) {
        ans = "NO";
        break;
      }
    }
    System.out.println(ans);
  }
}