alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZÆØÅ"
string = "ZQOØQOØ, RI."

def decodechar(char,shift):
    if char in alphabet:
        i = alphabet.index(char)
        return alphabet[(i+shift) % len(alphabet)]
    else:
        return char

for shift in range(len(alphabet)):
    print("".join([decodechar(c,shift) for c in string]), "Shift:", shift)