a = str(eval(input()))

b = a.upper()

if(a==b):

  print("A")

else:

  print("a")



    

a = str(eval(input()))

x = "QWERTYUIOPASDFGHJKLZXCVBNM"

if(a in x):

  print("A")

else:

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

a = str(eval(input()))
x = "QWERTYUIOPASDFGHJKLZXCVBNM"
if a in x:
    print("A")
else:
    print("a")

-b = a.upper() -if a == b: +x = "QWERTYUIOPASDFGHJKLZXCVBNM" +if a in x: