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

class No_69{
	public static void main(String[] args){
		
		Scanner sc = new Scanner(System.in);
		String a = sc.next();
		String b = sc.next();
		char[] arraya = new char[a.length()];
		char[] arrayb = new char[b.length()];
		int cnt = 0;
		
		for(int i = 0;i < a.length();i++){
		arraya[i] = a.charAt(i);
		arrayb[i] = b.charAt(i);
		}
		
		Arrays.sort(arraya);
		Arrays.sort(arrayb);
		
		for(int i = 0;i < a.length();i++){
		if(arraya[i] != arrayb[i]){
		break;
		}
		cnt++;
		}
		
		if(cnt == a.length()){
		System.out.println("YES");
		}else{
		System.out.println("NO");
		}
	}
}