diff --git a/2015-oc/Makefile b/2015-oc/Makefile
index 988239a..3da5414 100644
--- a/2015-oc/Makefile
+++ b/2015-oc/Makefile
@@ -4,4 +4,4 @@ blue.pdf: blue.tex
 	pdflatex $<
 
 clean:
-	-rm -f *.aux *.log *.out
+	-rm -f *.aux *.log *.out *.snm *.toc *.nav