container-with-most-water

Author: han

container-with-most-water/han.exs

@@ -0,0 +1,23 @@
+defmodule Solution do
+  @spec max_area(height :: [integer]) :: integer
+  def max_area(heights) do
+    List.to_tuple(heights) |> max_area(0, length(heights) - 1, 0)
+  end
+
+  defp max_area(_, left_pointer, right_pointer, answer) when left_pointer == right_pointer, do: answer
+
+  defp max_area(heights, left_pointer, right_pointer, answer) do
+    lh = elem(heights, left_pointer)
+    rh = elem(heights, right_pointer)
+    height = min(lh, rh)
+    width = right_pointer - left_pointer
+
+    new_max_area = max(answer, height * width)
+    cond do
+      lh < rh ->
+        max_area(heights, left_pointer + 1, right_pointer, new_max_area)
+      true ->
+        max_area(heights, left_pointer, right_pointer - 1, new_max_area)
+    end
+  end
+end