Answer: Secret Code #86

The secret message says:

NICE WORK!

The shift was 11.

The secret note decoded: NICE WORK!
The note, decoded.

Letter by letter

Secret letterCHNPTVYZ
Real letterRWCEIKNO

Decode it with Python

This program does the decoding for you. Change the secret and the shift to crack other messages!

secret = "YTNP HZCV!"
shift = 11
message = ""

for letter in secret:
    if letter.isalpha():
        number = (ord(letter) - ord("A") - shift) % 26
        message = message + chr(number + ord("A"))
    else:
        message = message + letter

print(message)

When you run it, it prints:

NICE WORK!

Did you know? Shift codes are very old. A Roman writer called Suetonius said that Julius Caesar wrote secret letters by shifting the alphabet by three. That’s why it’s often called the Caesar cipher.