a = input()
b = input()

length = len(a)

a_dict = {}
b_dict = {}

for i in range(length):
    if a[i] in a_dict.keys():
        a_dict[a[i]] += 1
    else:
        a_dict[a[i]] = 1
    
    if b[i] in b_dict.keys():
        b_dict[b[i]] += 1
    else:
        b_dict[b[i]] = 1

isSame = True
for key in a_dict.keys():
    if key not in b_dict:
        isSame = False
        print("NO")
        break
    if a_dict[key] != b_dict[key]:
        isSame = False
        print("NO")
        break

if isSame:
    print("YES")