50 lines
1.3 KiB
Markdown
50 lines
1.3 KiB
Markdown
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# Run-Length Encoding
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Welcome to Run-Length Encoding on Exercism's Elixir Track.
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If you need help running the tests or submitting your code, check out `HELP.md`.
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## Instructions
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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 (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 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 the letters A through Z (either lower or upper case) and whitespace.
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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.
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## Source
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### Created by
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- @Teapane
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### Contributed to by
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- @angelikatyborska
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- @CoderDennis
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- @Cohen-Carlisle
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- @dalexj
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- @daveyarwood
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- @devonestes
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- @lex57ukr
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- @lpil
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- @neenjaw
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- @parkerl
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- @sotojuan
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- @waiting-for-dev
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### Based on
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Wikipedia - https://en.wikipedia.org/wiki/Run-length_encoding
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