61 lines
1.6 KiB
Markdown
61 lines
1.6 KiB
Markdown
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# Run Length Encoding
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Implement run-length encoding and decoding.
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Run-length encoding (RLE) is a simple form of data compression, where runs
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(consecutive data elements) are replaced by just one data value and count.
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For example we can represent the original 53 characters with only 13.
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```text
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"WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWB" -> "12WB12W3B24WB"
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```
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RLE allows the original data to be perfectly reconstructed from
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the compressed data, which makes it a lossless data compression.
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```text
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"AABCCCDEEEE" -> "2AB3CD4E" -> "AABCCCDEEEE"
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```
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For simplicity, you can assume that the unencoded string will only contain
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the letters A through Z (either lower or upper case) and whitespace. This way
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data to be encoded will never contain any numbers and numbers inside data to
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be decoded always represent the count for the following character.
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## Setup
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Go through the setup instructions for Javascript to
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install the necessary dependencies:
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[https://exercism.io/tracks/javascript/installation](https://exercism.io/tracks/javascript/installation)
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## Requirements
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Install assignment dependencies:
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```bash
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$ npm install
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```
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## Making the test suite pass
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Execute the tests with:
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```bash
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$ npm test
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```
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In the test suites all tests but the first have been skipped.
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Once you get a test passing, you can enable the next one by
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changing `xtest` to `test`.
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## Source
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Wikipedia [https://en.wikipedia.org/wiki/Run-length_encoding](https://en.wikipedia.org/wiki/Run-length_encoding)
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## Submitting Incomplete Solutions
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It's possible to submit an incomplete solution so you can see how others have completed the exercise.
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