1 exercism fetch rust rotational-cipher

# Rotational Cipher

Create an implementation of the rotational cipher, also sometimes called the Caesar cipher.

The Caesar cipher is a simple shift cipher that relies on transposing all the letters in the alphabet using an integer key between 0 and 26. Using a key of 0 or 26 will always yield the same output due to modular arithmetic. The letter is shifted for as many values as the value of the key.

The general notation for rotational ciphers is ROT + <key>. The most commonly used rotational cipher is ROT13.

A ROT13 on the Latin alphabet would be as follows:

 1 2 Plain: abcdefghijklmnopqrstuvwxyz Cipher: nopqrstuvwxyzabcdefghijklm

It is stronger than the Atbash cipher because it has 27 possible keys, and 25 usable keys.

Ciphertext is written out in the same formatting as the input including spaces and punctuation.

## Examples

• ROT5 omg gives trl
• ROT0 c gives c
• ROT26 Cool gives Cool
• ROT13 The quick brown fox jumps over the lazy dog. gives Gur dhvpx oebja sbk whzcf bire gur ynml qbt.
• ROT13 Gur dhvpx oebja sbk whzcf bire gur ynml qbt. gives The quick brown fox jumps over the lazy dog.

## Rust Installation

Refer to the exercism help page for Rust installation and learning resources.

## Writing the Code

Execute the tests with:

 1 \$ cargo test

All but the first test have been ignored. After you get the first test to pass, remove the ignore flag (#[ignore]) from the next test and get the tests to pass again. The test file is located in the tests directory. You can also remove the ignore flag from all the tests to get them to run all at once if you wish.

Make sure to read the Modules chapter if you haven't already, it will help you with organizing your files.

## Feedback, Issues, Pull Requests

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## Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.