A = input()
B = input()

def runlength2(S):
    R = {}
    LS = len(S)
    for i in range(LS):
        if R.get(S[i]):
            R[S[i]] += 1
        else:
            R[S[i]] =1
    return R

AA = runlength2(A)
BB = runlength2(B)

for key, val in AA.items():
    if BB.get(key):
        if BB[key] != val:
            print('NO')
            exit()
    else:
        print('NO')
        exit()
print('YES')