--- a/progs/sudoku.scala	Mon Jul 21 16:38:07 2025 +0100
+++ b/progs/sudoku.scala	Fri Sep 12 10:36:07 2025 +0100
@@ -1,11 +1,13 @@
 // Sudoku
 //========
 
-// call parallel version with
+// you can call the parallel version with
+//
+//   scala -cp scala-parallel-collections_3-1.0.4.jar sudoku.scala
 //
-// scala -cp scala-parallel-collections_3-1.0.4.jar sudoku.scala
+// or with java directly 
 //
-// java -cp .:scala3-library_3-3.2.2.jar:scala-parallel-collections_3-1.0.4.jar Sudoku
+//   java -cp .:scala3-library_3-3.2.2.jar:scala-parallel-collections_3-1.0.4.jar Sudoku