## On the Subject of the White Cipher

White as the driven snow, this cipher knows no bounds to give defusers a hard time.

On the module, you will see 3 screens, a keyboard, 2 arrows, and a submit button that displays the current page you’re on.

Pressing the right arrow takes you to the next page. Pressing the left arrow takes you to the previous page. There is a total of 2 pages.

On page 1, the top screen shows a 6 letter encrypted word, the middle screen shows a number.

On page 2, the top and middle screen shows an 8 letter key.

Follow the mechanics down below to decrypt your word:

### Step 1: Base Caesar Cipher

For this, you’re going to need the encrypted word on the top screen, and the number on the middle screen, both from page 1.

The number in the middle screen was used to shift the letters of the encrypted word. However the number is not in base 10.

To figure out which base the number is in, take the sum of the alphanumeric positions of the letters of the encrypted word (A = 1, B = 2, ... Z = 26). Then modulo 8 the sum (subtract 8 to the sum until the number is between 0 - 7), then add 2. The resulting number is the base of the number.

To convert the number to base 10, follow the steps below:

- 1: Above each of the digits in your number (middle screen), list the power of the base that the digit represents. Start at 0 on the right and increment by 1 as you go left for each digit.
- 2: Multiply each digit by the power of the base.
- 3: Add all the numbers together to get your base 10 number.

After converting the number to base 10, add the number to each letter of the encrypted word using its alphanumeric position (A = 1, B = 2...Z = 26), modulo 26, and convert the number back to a letter to get a new encrypted word.

#### Example

Encrypted word: DSIHDG

Number: 1104

Base: 4 + 19 + 9 + 8 + 4 + 7 = 51 % 8 = 3 + 2 = 5