s = eval(input())

if s == s.upper():

    print("A")

else:

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

if a == a.lower():

    print("a")

else:

    print("A")
s = eval(input())
if s == s.upper():
    print("A")
else:
    print("a")

a = eval(input())
if a == a.lower():
    print("a")
else:
    print("A")

-s = eval(input()) -if s == s.upper(): +a = eval(input()) +if a == a.lower(): +    print("a") +else: -else: -    print("a")