From 58eac331ab05c7fccda379d047e3d2f1ac1e7c5b Mon Sep 17 00:00:00 2001 From: Danylo Negrienko Date: Sun, 7 Jul 2024 00:41:15 -0400 Subject: [PATCH] pascals_triangle --- elixir/pascals-triangle/.exercism/config.json | 30 ++++ .../pascals-triangle/.exercism/metadata.json | 1 + elixir/pascals-triangle/.formatter.exs | 4 + elixir/pascals-triangle/.gitignore | 24 +++ elixir/pascals-triangle/HELP.md | 75 +++++++++ elixir/pascals-triangle/README.md | 41 +++++ .../pascals-triangle/lib/pascals_triangle.ex | 19 +++ elixir/pascals-triangle/mix.exs | 28 ++++ .../test/pascals_triangle_test.exs | 152 ++++++++++++++++++ elixir/pascals-triangle/test/test_helper.exs | 2 + 10 files changed, 376 insertions(+) create mode 100644 elixir/pascals-triangle/.exercism/config.json create mode 100644 elixir/pascals-triangle/.exercism/metadata.json create mode 100644 elixir/pascals-triangle/.formatter.exs create mode 100644 elixir/pascals-triangle/.gitignore create mode 100644 elixir/pascals-triangle/HELP.md create mode 100644 elixir/pascals-triangle/README.md create mode 100644 elixir/pascals-triangle/lib/pascals_triangle.ex create mode 100644 elixir/pascals-triangle/mix.exs create mode 100644 elixir/pascals-triangle/test/pascals_triangle_test.exs create mode 100644 elixir/pascals-triangle/test/test_helper.exs diff --git a/elixir/pascals-triangle/.exercism/config.json b/elixir/pascals-triangle/.exercism/config.json new file mode 100644 index 0000000..b8c23dc --- /dev/null +++ b/elixir/pascals-triangle/.exercism/config.json @@ -0,0 +1,30 @@ +{ + "authors": [ + "dalexj" + ], + "contributors": [ + "amencarini", + "angelikatyborska", + "Cohen-Carlisle", + "devonestes", + "lpil", + "neenjaw", + "parkerl", + "sotojuan", + "waiting-for-dev" + ], + "files": { + "solution": [ + "lib/pascals_triangle.ex" + ], + "test": [ + "test/pascals_triangle_test.exs" + ], + "example": [ + ".meta/example.ex" + ] + }, + "blurb": "Compute Pascal's triangle up to a given number of rows.", + "source": "Pascal's Triangle at Wolfram Math World", + "source_url": "https://www.wolframalpha.com/input/?i=Pascal%27s+triangle" +} diff --git a/elixir/pascals-triangle/.exercism/metadata.json b/elixir/pascals-triangle/.exercism/metadata.json new file mode 100644 index 0000000..fd2ed0c --- /dev/null +++ b/elixir/pascals-triangle/.exercism/metadata.json @@ -0,0 +1 @@ +{"track":"elixir","exercise":"pascals-triangle","id":"71d888253d44412db03d365e545aa233","url":"https://exercism.org/tracks/elixir/exercises/pascals-triangle","handle":"negrienko","is_requester":true,"auto_approve":false} \ No newline at end of file diff --git a/elixir/pascals-triangle/.formatter.exs b/elixir/pascals-triangle/.formatter.exs new file mode 100644 index 0000000..d2cda26 --- /dev/null +++ b/elixir/pascals-triangle/.formatter.exs @@ -0,0 +1,4 @@ +# Used by "mix format" +[ + inputs: ["{mix,.formatter}.exs", "{config,lib,test}/**/*.{ex,exs}"] +] diff --git a/elixir/pascals-triangle/.gitignore b/elixir/pascals-triangle/.gitignore new file mode 100644 index 0000000..f88b8fb --- /dev/null +++ b/elixir/pascals-triangle/.gitignore @@ -0,0 +1,24 @@ +# The directory Mix will write compiled artifacts to. +/_build/ + +# If you run "mix test --cover", coverage assets end up here. +/cover/ + +# The directory Mix downloads your dependencies sources to. +/deps/ + +# Where third-party dependencies like ExDoc output generated docs. +/doc/ + +# Ignore .fetch files in case you like to edit your project deps locally. +/.fetch + +# If the VM crashes, it generates a dump, let's ignore it too. +erl_crash.dump + +# Also ignore archive artifacts (built via "mix archive.build"). +*.ez + +# Ignore package tarball (built via "mix hex.build"). +pascals_triangle-*.tar + diff --git a/elixir/pascals-triangle/HELP.md b/elixir/pascals-triangle/HELP.md new file mode 100644 index 0000000..310c4a2 --- /dev/null +++ b/elixir/pascals-triangle/HELP.md @@ -0,0 +1,75 @@ +# Help + +## Running the tests + +From the terminal, change to the base directory of the exercise then execute the tests with: + +```bash +$ mix test +``` + +This will execute the test file found in the `test` subfolder -- a file ending in `_test.exs` + +Documentation: + +* [`mix test` - Elixir's test execution tool](https://hexdocs.pm/mix/Mix.Tasks.Test.html) +* [`ExUnit` - Elixir's unit test library](https://hexdocs.pm/ex_unit/ExUnit.html) + +## Pending tests + +In test suites of practice exercises, all but the first test have been tagged to be 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 +``` + +If you wish to run all tests at once, you can include all skipped test by using the `--include` flag on the `mix test` command: + +```bash +$ mix test --include pending +``` + +Or, you can enable all the tests by commenting out the `ExUnit.configure` line in the file `test/test_helper.exs`. + +```elixir +# ExUnit.configure(exclude: :pending, trace: true) +``` + +## Useful `mix test` options + +* `test/.exs:LINENUM` - runs only a single test, the test from `.exs` whose definition is on line `LINENUM` +* `--failed` - runs only tests that failed the last time they ran +* `--max-failures` - the suite stops evaluating tests when this number of test failures +is reached +* `--seed 0` - disables randomization so the tests in a single file will always be ran +in the same order they were defined in + +## Submitting your solution + +You can submit your solution using the `exercism submit lib/pascals_triangle.ex` command. +This command will upload your solution to the Exercism website and print the solution page's URL. + +It's possible to submit an incomplete solution which allows you to: + +- See how others have completed the exercise +- Request help from a mentor + +## Need to get help? + +If you'd like help solving the exercise, check the following pages: + +- The [Elixir track's documentation](https://exercism.org/docs/tracks/elixir) +- The [Elixir track's programming category on the forum](https://forum.exercism.org/c/programming/elixir) +- [Exercism's programming category on the forum](https://forum.exercism.org/c/programming/5) +- The [Frequently Asked Questions](https://exercism.org/docs/using/faqs) + +Should those resources not suffice, you could submit your (incomplete) solution to request mentoring. + +If you're stuck on something, it may help to look at some of the [available resources](https://exercism.org/docs/tracks/elixir/resources) out there where answers might be found. \ No newline at end of file diff --git a/elixir/pascals-triangle/README.md b/elixir/pascals-triangle/README.md new file mode 100644 index 0000000..263ea90 --- /dev/null +++ b/elixir/pascals-triangle/README.md @@ -0,0 +1,41 @@ +# Pascal's Triangle + +Welcome to Pascal's Triangle on Exercism's Elixir Track. +If you need help running the tests or submitting your code, check out `HELP.md`. + +## Instructions + +Compute Pascal's triangle up to a given number of rows. + +In Pascal's Triangle each number is computed by adding the numbers to the right and left of the current position in the previous row. + +```text + 1 + 1 1 + 1 2 1 + 1 3 3 1 +1 4 6 4 1 +# ... etc +``` + +## Source + +### Created by + +- @dalexj + +### Contributed to by + +- @amencarini +- @angelikatyborska +- @Cohen-Carlisle +- @devonestes +- @lpil +- @neenjaw +- @parkerl +- @sotojuan +- @waiting-for-dev + +### Based on + +Pascal's Triangle at Wolfram Math World - https://www.wolframalpha.com/input/?i=Pascal%27s+triangle \ No newline at end of file diff --git a/elixir/pascals-triangle/lib/pascals_triangle.ex b/elixir/pascals-triangle/lib/pascals_triangle.ex new file mode 100644 index 0000000..7f39d02 --- /dev/null +++ b/elixir/pascals-triangle/lib/pascals_triangle.ex @@ -0,0 +1,19 @@ +defmodule PascalsTriangle do + @doc """ + Calculates the rows of a pascal triangle + with the given height + """ + @spec rows(integer) :: [[integer]] + def rows(num) do + 1..num + |> Enum.reduce([[]], fn _, triangle -> [next(hd(triangle)) | triangle] end) + |> Enum.take(num) + |> Enum.reverse + end + + defp next(from, acc \\ []) + defp next([], _acc), do: [1] + defp next([1], _acc), do: [1, 1] + defp next([one, two | []], acc), do: [1 | Enum.reverse([1, one + two | acc])] + defp next([one, two | rest], acc), do: next([two | rest], [one + two | acc]) +end diff --git a/elixir/pascals-triangle/mix.exs b/elixir/pascals-triangle/mix.exs new file mode 100644 index 0000000..d939fe5 --- /dev/null +++ b/elixir/pascals-triangle/mix.exs @@ -0,0 +1,28 @@ +defmodule PascalsTriangle.MixProject do + use Mix.Project + + def project do + [ + app: :pascals_triangle, + version: "0.1.0", + # elixir: "~> 1.8", + start_permanent: Mix.env() == :prod, + deps: deps() + ] + end + + # Run "mix help compile.app" to learn about applications. + def application do + [ + extra_applications: [:logger] + ] + end + + # Run "mix help deps" to learn about dependencies. + defp deps do + [ + # {:dep_from_hexpm, "~> 0.3.0"}, + # {:dep_from_git, git: "https://github.com/elixir-lang/my_dep.git", tag: "0.1.0"} + ] + end +end diff --git a/elixir/pascals-triangle/test/pascals_triangle_test.exs b/elixir/pascals-triangle/test/pascals_triangle_test.exs new file mode 100644 index 0000000..2625922 --- /dev/null +++ b/elixir/pascals-triangle/test/pascals_triangle_test.exs @@ -0,0 +1,152 @@ +defmodule PascalsTriangleTest do + use ExUnit.Case + + test "one row" do + assert PascalsTriangle.rows(1) == [[1]] + end + + test "two rows" do + assert PascalsTriangle.rows(2) == [[1], [1, 1]] + end + + test "three rows" do + assert PascalsTriangle.rows(3) == [[1], [1, 1], [1, 2, 1]] + end + + test "four rows" do + assert PascalsTriangle.rows(4) == [[1], [1, 1], [1, 2, 1], [1, 3, 3, 1]] + end + + test "five rows" do + assert PascalsTriangle.rows(5) == [[1], [1, 1], [1, 2, 1], [1, 3, 3, 1], [1, 4, 6, 4, 1]] + end + + test "six rows" do + assert PascalsTriangle.rows(6) == [ + [1], + [1, 1], + [1, 2, 1], + [1, 3, 3, 1], + [1, 4, 6, 4, 1], + [1, 5, 10, 10, 5, 1] + ] + end + + test "ten rows" do + assert PascalsTriangle.rows(10) == [ + [1], + [1, 1], + [1, 2, 1], + [1, 3, 3, 1], + [1, 4, 6, 4, 1], + [1, 5, 10, 10, 5, 1], + [1, 6, 15, 20, 15, 6, 1], + [1, 7, 21, 35, 35, 21, 7, 1], + [1, 8, 28, 56, 70, 56, 28, 8, 1], + [1, 9, 36, 84, 126, 126, 84, 36, 9, 1] + ] + end + + test "20 rows" do + assert PascalsTriangle.rows(20) == [ + [1], + [1, 1], + [1, 2, 1], + [1, 3, 3, 1], + [1, 4, 6, 4, 1], + [1, 5, 10, 10, 5, 1], + [1, 6, 15, 20, 15, 6, 1], + [1, 7, 21, 35, 35, 21, 7, 1], + [1, 8, 28, 56, 70, 56, 28, 8, 1], + [1, 9, 36, 84, 126, 126, 84, 36, 9, 1], + [1, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1], + [1, 11, 55, 165, 330, 462, 462, 330, 165, 55, 11, 1], + [1, 12, 66, 220, 495, 792, 924, 792, 495, 220, 66, 12, 1], + [1, 13, 78, 286, 715, 1287, 1716, 1716, 1287, 715, 286, 78, 13, 1], + [1, 14, 91, 364, 1001, 2002, 3003, 3432, 3003, 2002, 1001, 364, 91, 14, 1], + [1, 15, 105, 455, 1365, 3003, 5005, 6435, 6435, 5005, 3003, 1365, 455, 105, 15, 1], + [ + 1, + 16, + 120, + 560, + 1820, + 4368, + 8008, + 11440, + 12870, + 11440, + 8008, + 4368, + 1820, + 560, + 120, + 16, + 1 + ], + [ + 1, + 17, + 136, + 680, + 2380, + 6188, + 12376, + 19448, + 24310, + 24310, + 19448, + 12376, + 6188, + 2380, + 680, + 136, + 17, + 1 + ], + [ + 1, + 18, + 153, + 816, + 3060, + 8568, + 18564, + 31824, + 43758, + 48620, + 43758, + 31824, + 18564, + 8568, + 3060, + 816, + 153, + 18, + 1 + ], + [ + 1, + 19, + 171, + 969, + 3876, + 11628, + 27132, + 50388, + 75582, + 92378, + 92378, + 75582, + 50388, + 27132, + 11628, + 3876, + 969, + 171, + 19, + 1 + ] + ] + end +end diff --git a/elixir/pascals-triangle/test/test_helper.exs b/elixir/pascals-triangle/test/test_helper.exs new file mode 100644 index 0000000..35fc5bf --- /dev/null +++ b/elixir/pascals-triangle/test/test_helper.exs @@ -0,0 +1,2 @@ +ExUnit.start() +ExUnit.configure(exclude: :pending, trace: true)