# print('a' if 'a' <= input() <= 'z' else 'A')

print((['A','a']['a' <= eval(input()) <= 'z']))

# print('a' if 'a' <= input() <= 'z' else 'A')

# print(['A','a']['a' <= input() <= 'z'])

print((['A','a'][input().islower()]))

# print('a' if 'a' <= input() <= 'z' else 'A')
print((["A", "a"]["a" <= eval(input()) <= "z"]))

# print('a' if 'a' <= input() <= 'z' else 'A')
# print(['A','a']['a' <= input() <= 'z'])
print((["A", "a"][input().islower()]))

-print((["A", "a"]["a" <= eval(input()) <= "z"])) +# print(['A','a']['a' <= input() <= 'z']) +print((["A", "a"][input().islower()]))