• 32

Learning Opportunities

This puzzle can be solved using the following concepts. Practice using these concepts and improve your skills.



[Crackling static]
Agent X to Base, respond, over.
[Base responds]
Base here, we read you, Agent X, over.
[Agent X]
I've intercepted an enemy message, but it appears to be encoded with a Caesar cipher. I need to decrypt it quickly to foil their plans. The problem is, I don't know the key... Fortunately, I have a word that should appear in the decrypted message. I need your help to find the key and the original message, over.
Understood, Agent X. Send us the data, and we'll decrypt the message, over.

The Caesar cipher used by Agent X works by substituting each character in the original message by another character a fixed number of positions (called the key) down the ASCII code range of 32 to 126 on a wrap-around basis. key is non-negative in this puzzle.

For example, with a key of 3:
- a becomes d
- w becomes z
- x becomes {
- ! becomes $
- , becomes /
- SP (space character) becomes #
- A becomes D
- W becomes Z
- ~ becomes "

Words are always separated by SP,, ., ?, ;, : and !
Line 1 ciphertext : The encrypted message to be decrypted.
Line 2 word : A word that is guaranteed to appear in the decrypted message
Line 1 key : The key of the Caesar cipher.
Line 2 plaintext : The decrypted message.
Length of word<25
Test, test, hello!

A higher resolution is required to access the IDE