diff --git a/src/Years/Y2015/Day1.idr b/src/Years/Y2015/Day1.idr
index cbe81d0..09db409 100644
--- a/src/Years/Y2015/Day1.idr
+++ b/src/Years/Y2015/Day1.idr
@@ -4,7 +4,19 @@ import Control.Eff
 
 import Runner
 
-part1 : Eff (PartEff String) ((), ())
+%default total
+
+trackFloor : (start : Integer) -> (xs : List Char) -> Integer
+trackFloor start [] = start
+trackFloor start ('(' :: xs) = trackFloor (start + 1) xs
+trackFloor start (')' :: xs) = trackFloor (start - 1) xs
+trackFloor start (x :: xs) = trackFloor start xs
+
+part1 : Eff (PartEff String) (Integer, ())
+part1 = do
+  input <- map unpack $ askAt "input"
+  let output = trackFloor 0 input
+  pure (output, ())
 
 export
 day1 : Day