import java.util.Arrays;
import java.util.Scanner;
 
class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String a = sc.next();
		String b = sc.next();
		char[] aa = a.toCharArray();
		char[] bb = b.toCharArray();
		Arrays.sort(aa);
		Arrays.sort(bb);
		for(int i = 0;i < aa.length;i++){
			if(aa[i]!=bb[i]){
				System.out.println("NO");
				System.exit(0);
			}
		}
		System.out.println("YES");
	}
}