import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;

public class No069 {
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);

		String a = sc.nextLine();
		String b = sc.nextLine();

		List<String> al = new ArrayList<String>();
		List<String> bl = new ArrayList<String>();

		for(int i=0; i<a.length(); i++){
			al.add(a.substring(i, i+1));
			bl.add(b.substring(i, i+1));
		}
		Collections.sort(al);
		Collections.sort(bl);
		if(al.equals(bl)){
			System.out.println("YES");
		}else{
			System.out.println("NO");
		}
	}
}