diff --git a/src/main/scala/eu/sim642/adventofcode2024/Day25.scala b/src/main/scala/eu/sim642/adventofcode2024/Day25.scala
index b083668a..c74ccb1a 100644
--- a/src/main/scala/eu/sim642/adventofcode2024/Day25.scala
+++ b/src/main/scala/eu/sim642/adventofcode2024/Day25.scala
@@ -8,16 +8,21 @@ object Day25 {
   def isKey(grid: Grid[Boolean]): Boolean =
     grid.head.forall(identity)
 
+  def fits(key: Grid[Boolean], lock: Grid[Boolean]): Boolean =
+    key.correspondsGrid(lock)((k, l) => !(k && l))
+
   def countLockKeyFits(lockKeys: Seq[Grid[Boolean]]): Int = {
     val (keys, locks) = lockKeys.partition(isKey)
     (for {
       key <- keys
       lock <- locks
-      if key.correspondsGrid(lock)((k, l) => !(k && l))
+      if fits(key, lock)
     } yield ()).size
   }
 
-  def parseLockKeys(input: String): Seq[Grid[Boolean]] = input.split("\n\n").map(_.linesIterator.map(_.map(_ == '#').toVector).toVector).toSeq
+  def parseLockKey(s: String): Grid[Boolean] = s.linesIterator.map(_.map(_ == '#').toVector).toVector
+
+  def parseLockKeys(input: String): Seq[Grid[Boolean]] = input.split("\n\n").map(parseLockKey).toSeq
 
   lazy val input: String = scala.io.Source.fromInputStream(getClass.getResourceAsStream("day25.txt")).mkString.trim