import string
key = 5
clearText = "Veni vidi vici"
print(clearText)
ciphertext = ""
for letter in clearText.upper():
    index = string.ascii_uppercase.find(letter)
    if index != -1:  # -1 means not found, "!=" means not equal (ungleich) 
        cIndex = (index + key) % 26
        letter = string.ascii_uppercase[cIndex]
    ciphertext = ciphertext + letter
print(ciphertext)