65 lines
1.8 KiB
Markdown
65 lines
1.8 KiB
Markdown
# Triangle
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Determine if a triangle is equilateral, isosceles, or scalene.
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An _equilateral_ triangle has all three sides the same length.
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An _isosceles_ triangle has at least two sides the same length. (It is sometimes
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specified as having exactly two sides the same length, but for the purposes of
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this exercise we'll say at least two.)
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A _scalene_ triangle has all sides of different lengths.
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## Note
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For a shape to be a triangle at all, all sides have to be of length > 0, and
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the sum of the lengths of any two sides must be greater than or equal to the
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length of the third side. See [Triangle Inequality](https://en.wikipedia.org/wiki/Triangle_inequality).
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## Dig Deeper
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The case where the sum of the lengths of two sides _equals_ that of the
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third is known as a _degenerate_ triangle - it has zero area and looks like
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a single line. Feel free to add your own code/tests to check for degenerate triangles.
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## Running tests
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Execute the tests with:
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```bash
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$ elixir triangle_test.exs
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```
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### Pending tests
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In the test suites, all but the first test have been skipped.
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Once you get a test passing, you can unskip the next one by
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commenting out the relevant `@tag :pending` with a `#` symbol.
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For example:
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```elixir
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# @tag :pending
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test "shouting" do
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assert Bob.hey("WATCH OUT!") == "Whoa, chill out!"
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end
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```
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Or, you can enable all the tests by commenting out the
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`ExUnit.configure` line in the test suite.
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```elixir
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# ExUnit.configure exclude: :pending, trace: true
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```
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For more detailed information about the Elixir track, please
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see the [help page](http://exercism.io/languages/elixir).
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## Source
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The Ruby Koans triangle project, parts 1 & 2 [http://rubykoans.com](http://rubykoans.com)
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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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