diff --git a/.gitignore b/.gitignore
index c412b8a57069be211d8b1e9eaac6d673a1f8ad7a..e9a0aac656c735bed738c06282071c5a397965e3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -67,9 +67,10 @@ Temporary Items
 .apdisk
 
 ## project specific files and directories:
-output/*.dat
-output/*.txt
-input/*.txt
+output/*.
+!output/.gitkeep
+input/*
+!input/.gitkeep
 .idea
 backup/
 samsim.x
diff --git a/input/.gitkeep b/input/.gitkeep
new file mode 100644
index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
diff --git a/output/.gitkeep b/output/.gitkeep
new file mode 100644
index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391