diff --git a/2020/day01/ex1.bash b/2020/day01/ex1.bash
index 0594dc5..4f1d50e 100755
--- a/2020/day01/ex1.bash
+++ b/2020/day01/ex1.bash
@@ -2,7 +2,7 @@
 #
 # ex1.bash: Advent2020 game, day 1/game 1
 
-CMD=$(basename "$0")
+CMD=${0##*/}
 
 readarray -t numbers
 
diff --git a/2020/day01/ex2-sort.bash b/2020/day01/ex2-sort.bash
index 122deef..279ef38 100755
--- a/2020/day01/ex2-sort.bash
+++ b/2020/day01/ex2-sort.bash
@@ -2,7 +2,7 @@
 #
 # ex2-sort.bash: Advent2020 game, day 1/game 2, with sort.
 
-CMD=$(basename "$0")
+CMD=${0##*/}
 
 readarray -t numbers <<< "$(sort -n)"
 
diff --git a/2020/day01/ex2.bash b/2020/day01/ex2.bash
index c528141..2942bee 100755
--- a/2020/day01/ex2.bash
+++ b/2020/day01/ex2.bash
@@ -2,7 +2,7 @@
 #
 # ex2.bash: Advent2020 game, day 1/game 2
 
-CMD=$(basename "$0")
+CMD=${0##*/}
 
 readarray -t numbers