def check_palindrome(s):
length = len(s)
if 1 < length:
for i in range(length // 2):
a, b = s[i], s[-(i + 1)]
if a != b:
return False
return True
S = input()
L = len(S)
is_palindrome = False
string_pair = []
if L == 1:
is_palindrome = True
string_pair.append(S)
else:
for i in range(1, len(S)):
A, B = S[:i], S[i:]
check_A = check_palindrome(A)
check_B = check_palindrome(B)
if check_A and check_B:
is_palindrome = True
string_pair.append((A, B))
break
if is_palindrome:
print(*string_pair[0])
else:
print('NO')