diff --git a/2021/day4/4a.py b/2021/day4/4.py
similarity index 100%
rename from 2021/day4/4a.py
rename to 2021/day4/4.py
diff --git a/README.md b/README.md
index 017ab44..4538401 100644
--- a/README.md
+++ b/README.md
@@ -1,13 +1,13 @@
 my solutions for the [Advent of Code](https://adventofcode.com/)
 
-in progress: 
+in progress:\
 2021 (python)
 
-planned: 
-2022 (swift) 
-2020 (rust?) 
-2019 
-2018 
-2017 
-2016 
+planned:\
+2022 (swift)\
+2020 (rust?)\
+2019\
+2018\
+2017\
+2016\
 2015