Ceasers Cipher

This is the Decrypt 10 code which helped de-code the last clue.

The Caesar Cipher is one of the simplest and oldest encryption techniques. It shifts each letter in a message by a fixed number of positions in the alphabet. The shift key, an integer from 1 to 25, determines how many letters forward (or backward) each character moves. For example, with a key of 3, A becomes D, B becomes E, and Z becomes C. This shift uses modulo 26 arithmetic to wrap around the alphabet.

To encrypt a message, shift each letter forward by the key. Decryption is the reverse—shift backward by the same key. The cipher is case-insensitive, and non-letter characters usually remain unchanged. Due to only 25 possible keys, it's easy to break with brute force or frequency analysis, making it impractical for modern use but useful for learning cryptography.

Mathematically:

• Encryption: C = (P + K) mod 26

• Decryption: P = (C − K) mod 26
  Where A=0, B=1, ..., Z=25.

Project Summary:
We completed a scavenger hunt involving five clues encrypted with Caesar ciphers. After solving each clue, we received the next. The first four were simple and solvable by testing all 25 Caesar shifts with our code. The fifth clue was harder—it used a multi-digit key, where each letter was shifted by a different number.

We partially decoded the message to read: “The cow loves candies as much as…” Using the known starting phrase and the partial key “650806,” we figured out the rest by reverse-engineering the shifts. For example, decoding “f” to “w” meant a backward shift of 9. The final key was: 6508069278. But I reccived the scrambled code beacuse I was not at class that day.

The Five Clues:

1. Ms. Tran left her gate open.

2. Raul saw the cow with JH kids, eating mint candy.

3. Ms. Tran saw Ms. Sanchez with the same candy.

4. A candy wrapper with a phone number: 650806…

5. The cow loves candies as much as you do. It walked to Ms. Sanchez’s office for a snack.

SOUL Reflection

S - Strength: I efficiently used a decryption algorithm to test Caesar cipher shifts.

O - Opportunity: I could have solved the final key with more analysis instead of brute-forcing it.

U - Understanding: I gained a deeper understanding of encryption and now know how to create basic decryption tools.

L - Limitation: My decoder only works with known keys. It can’t try all combinations of multi-digit keys efficiently.

WISCR Reflection

Well-Rounded: I learned key coding skills, including loops and Python libraries.

Clear Communicator: I collaborated well with my partner to strategize and solve clues quickly.