Day One

day01.livemd

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+# Day01
+
+```elixir
+Mix.install([
+  {:kino, "~> 0.14.2"},
+  {:decimal, "~> 2.2"}
+])
+```
+
+## Input
+
+```elixir
+input = Kino.Input.textarea("Input")
+```
+
+## Parse Input
+
+```elixir
+input = 
+  input 
+  |> Kino.Input.read
+  |> String.split("\n")
+  |> Enum.map(fn l -> String.split(l, "   ") end)
+  |> List.foldl([[],[]], fn [x, y], [xa, ya] -> 
+    [[String.to_integer(x)| xa], [String.to_integer(y)| ya]] 
+  end)
+```
+
+## Part One
+
+```elixir
+input
+|> Enum.map(&Enum.sort/1)
+|> Enum.zip
+|> Enum.map(fn {x,y} -> abs(x - y) end)
+|> Enum.sum
+```
+
+## Part Two
+
+```elixir
+[x, y] = input
+
+f = Enum.frequencies(y)
+
+Enum.map(xfn xx -> xx * (f[xx] || 0) end)
+|> Enum.sum
+```