60 lines
1.8 KiB
Markdown
60 lines
1.8 KiB
Markdown
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# Resistor Color
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Welcome to Resistor Color 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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If you want to build something using a Raspberry Pi, you'll probably use _resistors_.
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For this exercise, you need to know two things about them:
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- Each resistor has a resistance value.
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- Resistors are small - so small in fact that if you printed the resistance value on them, it would be hard to read.
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To get around this problem, manufacturers print color-coded bands onto the resistors to denote their resistance values.
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Each band has a position and a numeric value.
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The first 2 bands of a resistor have a simple encoding scheme: each color maps to a single number.
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In this exercise you are going to create a helpful program so that you don't have to remember the values of the bands.
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These colors are encoded as follows:
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- Black: 0
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- Brown: 1
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- Red: 2
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- Orange: 3
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- Yellow: 4
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- Green: 5
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- Blue: 6
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- Violet: 7
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- Grey: 8
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- White: 9
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The goal of this exercise is to create a way:
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- to look up the numerical value associated with a particular color band
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- to list the different band colors
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Mnemonics map the colors to the numbers, that, when stored as an array, happen to map to their index in the array:
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Better Be Right Or Your Great Big Values Go Wrong.
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More information on the color encoding of resistors can be found in the [Electronic color code Wikipedia article][e-color-code].
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[e-color-code]: https://en.wikipedia.org/wiki/Electronic_color_code
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For this exercise, returning the list of colors is not required.
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## Source
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### Created by
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- @Bscruz19
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### Contributed to by
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- @angelikatyborska
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### Based on
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Maud de Vries, Erik Schierboom - https://github.com/exercism/problem-specifications/issues/1458
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