# Run Length Encoding

Implement run-length encoding and decoding.

Run-length encoding (RLE) is a simple form of data compression, where runs
(consecutive data elements) are replaced by just one data value and count.

For example we can represent the original 53 characters with only 13.

```text
"WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWB"  ->  "12WB12W3B24WB"
```

RLE allows the original data to be perfectly reconstructed from
the compressed data, which makes it a lossless data compression.

```text
"AABCCCDEEEE"  ->  "2AB3CD4E"  ->  "AABCCCDEEEE"
```

For simplicity, you can assume that the unencoded string will only contain
the letters A through Z (either lower or upper case) and whitespace. This way
data to be encoded will never contain any numbers and numbers inside data to
be decoded always represent the count for the following character.

## Getting Started
For installation and learning resources, refer to the
[exercism help page](http://exercism.io/languages/ocaml).

## Installation
To work on the exercises, you will need `Opam` and `Core`. Consult [opam](https://opam.ocaml.org) website for instructions on how to install `opam` for your OS. Once `opam` is installed open a terminal window and run the following command to install core:

```bash
opam install core
```

To run the tests you will need `OUnit`. Install it using `opam`:

```bash
opam install ounit
```

## Running Tests
A Makefile is provided with a default target to compile your solution and run the tests. At the command line, type:

```bash
make
```

## Interactive Shell
`utop` is a command line program which allows you to run Ocaml code interactively. The easiest way to install it is via opam:
```bash
opam install utop
```
Consult [utop](https://github.com/diml/utop/blob/master/README.md) for more detail.

## Feedback, Issues, Pull Requests
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If you have feedback about an exercise, or want to help implementing a new
one, head over there and create an issue.  We'll do our best to help you!

## Source

Wikipedia [https://en.wikipedia.org/wiki/Run-length_encoding](https://en.wikipedia.org/wiki/Run-length_encoding)

## Submitting Incomplete Solutions
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