rot-13

rot-13 is a simple letter substitution cipher that replaces a letter with the letter 13 letters after it in the alphabet. https://en.wikipedia.org/wiki/ROT13

Details

Converts alpha characters to there rotated-by-13 equivalent letter. Keeps cases. Ignores other characters.

Input:  ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz
Output: NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm

Example

Why did the chicken cross the road?
Gb trg gb gur bgure fvqr!

Transforming the entire text via ROT13 form, the answer to the joke is revealed:

Jul qvq gur puvpxra pebff gur ebnq?
To get to the other side!

Usage

var rot13 = require('./index.js');
console.log(rot13('abc')); // 'nop'

Tests

Just run ava.

ava