import java.util.*;
class mojinarabi{
	public static void main(String args[]){
		Scanner s = new Scanner(System.in);
		String a = s.next();
		String b = s.next();
		char A[] = a.toCharArray();
		char B[] = b.toCharArray();
		
		ArrayList<String> arrayA = new ArrayList<String>();
		ArrayList<String> arrayB = new ArrayList<String>();
		for(int i = 0; i < A.length; i++){
			arrayA.add(String.valueOf(A[i]));
			arrayB.add(String.valueOf(B[i]));
		}
		Collections.sort(arrayA);
		Collections.sort(arrayB);
		
		for(int i = 0; i < arrayA.size(); i++){
			if(!(arrayA.get(i).equals(arrayB.get(i)))){
				System.out.println("NO");
				System.exit(0);
			}
		}
		System.out.println("YES");
	}
}