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Contents
# 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.
```
"WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWB" -> "12WB12W3B24WB"
```
RLE allows the original data to be perfectly reconstructed from
the compressed data, which makes it a lossless data compression.
```
"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.
## Running tests
Execute the tests with:
```bash
$ elixir bob_test.exs
```
(Replace `bob_test.exs` with the name of the test file.)
### Pending tests
In the test suites, all but the first test have been skipped.
Once you get a test passing, you can unskip the next one by
commenting out the relevant `@tag :pending` with a `#` symbol.
For example:
```elixir
# @tag :pending
test "shouting" do
assert Bob.hey("WATCH OUT!") == "Whoa, chill out!"
end
```
Or, you can enable all the tests by commenting out the
`ExUnit.configure` line in the test suite.
```elixir
# ExUnit.configure exclude: :pending, trace: true
```
For more detailed information about the Elixir track, please
see the [help page](http://exercism.io/languages/elixir).
## Source
Wikipedia [https://en.wikipedia.org/wiki/Run-length_encoding](https://en.wikipedia.org/wiki/Run-length_encoding)
## Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
Version data entries
96 entries across 96 versions & 1 rubygems