#coding: utf-8

alp = [chr(i) for i in range(97, 97+26)]

a = eval(input())

if a in alp:

    print('a')

else:

    print('A')
# coding: utf-8

# Your code here!



c= eval(input())

a= ord('a')

alp = [chr(i) for i in range(a,a+26)]

#print(alp)

if c in alp:

    print('a')

else:

    print('A')
# coding: utf-8
alp = [chr(i) for i in range(97, 97 + 26)]
a = eval(input())
if a in alp:
    print("a")
else:
    print("A")

# coding: utf-8
# Your code here!
c = eval(input())
a = ord("a")
alp = [chr(i) for i in range(a, a + 26)]
# print(alp)
if c in alp:
    print("a")
else:
    print("A")

-alp = [chr(i) for i in range(97, 97 + 26)] -a = eval(input()) -if a in alp: +# Your code here! +c = eval(input()) +a = ord("a") +alp = [chr(i) for i in range(a, a + 26)] +# print(alp) +if c in alp: