A = input()
B = input()

n = len(A)

# A、Bをリストに
A_list = [A[i] for i in range(n)]
B_list = [B[i] for i in range(n)]

A_list.sort()
B_list.sort()

if A_list == B_list:
    print('YES')
else:
    print('NO')