Fix the regex to esclude only additional uppercase letters

Author: ike-agu

shell-pipelines/ls-grep/script-04.sh

@@ -5,5 +5,4 @@ set -euo pipefail
 # TODO: Write a command to count the number of files in the sample-files directory whose name starts with an upper case letter and doesn't contain any other upper case letters.
 # Your output should be the number 7.
 
-# ls sample-files | grep "^[A-Z][a-z]*$"
-ls sample-files | grep -c "^[A-Z][a-z]*$"
+ls sample-files | grep -c "^[A-Z][^A-Z]*$"