Standard input is empty

Standard output is empty

Exception in thread "main" java.lang.NullPointerException
	at scala.collection.mutable.ArrayOps$ofRef$.length$extension(ArrayOps.scala:114)
	at scala.collection.mutable.ArrayOps$ofRef.length(ArrayOps.scala:114)
	at scala.collection.SeqLike$class.size(SeqLike.scala:106)
	at scala.collection.mutable.ArrayOps$ofRef.size(ArrayOps.scala:108)
	at scala.collection.mutable.Builder$class.sizeHint(Builder.scala:69)
	at scala.collection.mutable.ListBuffer.sizeHint(ListBuffer.scala:45)
	at scala.collection.TraversableLike$class.to(TraversableLike.scala:628)
	at scala.collection.mutable.ArrayOps$ofRef.to(ArrayOps.scala:108)
	at scala.collection.TraversableOnce$class.toList(TraversableOnce.scala:257)
	at scala.collection.mutable.ArrayOps$ofRef.toList(ArrayOps.scala:108)
	at Main$delayedInit$body.apply(Main.scala:2)
	at scala.Function0$class.apply$mcV$sp(Function0.scala:40)
	at scala.runtime.AbstractFunction0.apply$mcV$sp(AbstractFunction0.scala:12)
	at scala.App$$anonfun$main$1.apply(App.scala:71)
	at scala.App$$anonfun$main$1.apply(App.scala:71)
	at scala.collection.immutable.List.foreach(List.scala:318)
	at scala.collection.generic.TraversableForwarder$class.foreach(TraversableForwarder.scala:32)
	at scala.App$class.main(App.scala:71)
	at Main$.main(Main.scala:1)
	at Main.main(Main.scala)