Sha256: f3df3c692f2a3a127dc37e6b39ac9cd3c3f03cebb48d76df5ed73b1db9aad55c

Contents?: true

Size: 1.73 KB

Versions: 55

Compression:

Stored size: 1.73 KB

Contents

# Atbash Cipher

Create an implementation of the atbash cipher, an ancient encryption system created in the Middle East.

The Atbash cipher is a simple substitution cipher that relies on
transposing all the letters in the alphabet such that the resulting
alphabet is backwards. The first letter is replaced with the last
letter, the second with the second-last, and so on.

An Atbash cipher for the Latin alphabet would be as follows:

```plain
Plain:  abcdefghijklmnopqrstuvwxyz
Cipher: zyxwvutsrqponmlkjihgfedcba
```

It is a very weak cipher because it only has one possible key, and it is
a simple monoalphabetic substitution cipher. However, this may not have
been an issue in the cipher's time.

Ciphertext is written out in groups of fixed length, the traditional group size
being 5 letters, and punctuation is excluded. This is to make it harder to guess
things based on word boundaries.

## Examples
- Encoding `test` gives `gvhg`
- Decoding `gvhg` gives `test`
- Decoding `gsvjf rxpyi ldmul cqfnk hlevi gsvoz abwlt` gives `thequickbrownfoxjumpsoverthelazydog`

## Setup

Go through the setup instructions for ECMAScript to
install the necessary dependencies:

http://exercism.io/languages/ecmascript/installation

## Requirements

Install assignment dependencies:

```bash
$ npm install
```

## Making the test suite pass

Execute the tests with:

```bash
$ npm test
```

In the test suites all tests but the first have been skipped.

Once you get a test passing, you can enable the next one by
changing `xtest` to `test`.


## Source

Wikipedia [http://en.wikipedia.org/wiki/Atbash](http://en.wikipedia.org/wiki/Atbash)

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

Version data entries

55 entries across 55 versions & 1 rubygems

Version Path
trackler-2.2.1.110 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.109 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.108 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.107 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.106 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.105 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.104 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.103 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.102 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.101 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.100 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.99 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.98 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.97 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.96 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.95 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.94 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.93 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.92 tracks/ecmascript/exercises/atbash-cipher/README.md
trackler-2.2.1.91 tracks/ecmascript/exercises/atbash-cipher/README.md