import java.util.Arrays;
import java.util.Scanner;


public class Main_yukicoder69 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        char[] a = sc.next().toCharArray();
        char[] b = sc.next().toCharArray();
        Arrays.sort(a);
        Arrays.sort(b);

        String aa = new String(a);
        String bb = new String(b);
        if (aa.equals(bb)) {
        	System.out.println("YES");
        } else {
        	System.out.println("NO");
        }
        
        sc.close();
    }
}