Elixir Cheat Sheet

{{lang-elixir}}
defmodule MergeSort do
  def sort([]), do: []
  def sort([x]), do: [x]

  def sort(list) do
    midpoint = div(length(list), 2)
    {left, right} = Enum.split(list, midpoint)
    
    new_left = sort(left)
    new_right = sort(right)
    
    merge(new_left, new_right)
  end

  def merge(left, []), do: left
  def merge([], right), do: right

  def merge([l | left], [r | right]) when l <= r do
    [l | merge(left, [r | right])]
  end

  def merge([l | left], [r | right]) do
    [r | merge([l | left], right)]
  end
end


MergeSort.sort([2,4,6,7,1,2,3,5])

{{lang-elixir}}
defmodule Sort do
  def insert([], x), do: [x]

  def insert([h | t], x) when x <= h, do: [x, h | t]  # Insert before if is lower 
  
  def insert([h | t], x), do: [h | insert(t, x)]  # Continue searching if is greater

  def insertion_sort([]), do: []
  
  def insertion_sort([h | t]) do
    sorted_tail = insertion_sort(t)
    insert(sorted_tail, h)
  end
end

Sort.insertion_sort([3, 1, 4, 2])

{{lang-elixir}}
defmodule Anagram do
  def anagram?(word1, word2) do
    Enum.sort(String.graphemes(word1)) == Enum.sort(String.graphemes(word2))
  end
end

IO.inspect(Anagram.anagram?("listen", "silent"))  # true

{{lang-elixir}}
defmodule Palindrome do
  def is_polindrome?(word) do
  word_to_charlist = to_charlist(word)
  (word_to_charlist == Enum.reverse(word_to_charlist))
  end
end

Palindrome.is_polindrome?("acbca")

{{lang-elixir}}
defmodule Fibonacci do
  def fib(n), do: fib(n, 0, 1)

  defp fib(0, a, _b), do: a
  defp fib(n, a, b), do: fib(n - 1, b, a + b)
end

IO.inspect(Fibonacci.fib(10))  # => 55