a = eval(input())

if ord(a) < 0x61:

    print('A')

else:

    print("a")
s = eval(input())

if ord(s) <= 0x5a:

    print("A")

else:

    print("a")
a = eval(input())
if ord(a) < 0x61:
    print("A")
else:
    print("a")

s = eval(input())
if ord(s) <= 0x5A:
    print("A")
else:
    print("a")

-a = eval(input()) -if ord(a) < 0x61: +s = eval(input()) +if ord(s) <= 0x5A: