Day 6

lib/day6/day6.ex

@@ -41,25 +41,21 @@ defmodule Day6 do
     str
     |> String.replace(~r/\s/, "")
     |> String.to_charlist()
-    |> Enum.into(MapSet.new())
+    |> MapSet.new()
   end
 
   def questions_with_all_yes(str) do
-    str
+    people =
-    |> String.split("\n")
+      str
-    |> Enum.map(fn person ->
+      |> String.split("\n")
-      person
+      |> Enum.map(fn person ->
-      |> String.to_charlist()
+        person
-      |> MapSet.new()
+        |> String.to_charlist()
-    end)
+        |> MapSet.new()
-    |> Enum.reduce(nil, fn person, acc ->
+      end)
-      case acc do
-        nil ->
-          person
 
-        _ ->
+    people
-          MapSet.intersection(acc, person)
+    |> Enum.drop(1)
-      end
+    |> Enum.reduce(List.first(people), &MapSet.intersection/2)
-    end)
   end
 end