Sha256: b60603a8eb560d2f48c70e95b55967399ece53e901018106e3b6b6b668b7290f

Contents?: true

Size: 1.49 KB

Versions: 76

Compression:

Stored size: 1.49 KB

Contents

# 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:

```text
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.`

## Setup

Go through the project setup instructions for Xcode using Swift:

http://exercism.io/languages/swift


## Source

Wikipedia [https://en.wikipedia.org/wiki/Caesar_cipher](https://en.wikipedia.org/wiki/Caesar_cipher)

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

Version data entries

76 entries across 76 versions & 1 rubygems

Version Path
trackler-2.2.1.180 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.179 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.178 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.177 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.176 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.175 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.174 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.173 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.172 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.171 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.170 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.169 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.167 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.166 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.165 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.164 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.163 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.162 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.161 tracks/swift/exercises/rotational-cipher/README.md
trackler-2.2.1.160 tracks/swift/exercises/rotational-cipher/README.md