alpha = eval(input())

if str.upper(alpha) == alpha:

  sol = "A"

else:

  sol = "a"

print(sol)
a = eval(input())

print(("a" if a.islower() else "A"))
alpha = eval(input())
if str.upper(alpha) == alpha:
    sol = "A"
else:
    sol = "a"
print(sol)

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

-alpha = eval(input()) -if str.upper(alpha) == alpha: -    sol = "A" -else: -    sol = "a" -print(sol) +a = eval(input()) +print(("a" if a.islower() else "A"))