added trailing lines + fixed script 4

Author: M-Abdoon

shell-pipelines/ls-grep/script-01.sh

@@ -4,4 +4,4 @@ set -euo pipefail
 
 # TODO: Write a command to output the names of the files in the sample-files directory whose name contains at least one upper case letter.
 # Your output should contain 11 files.
-ls sample-files | grep '[A-Z]'
+ls sample-files | grep '[A-Z]'

shell-pipelines/ls-grep/script-02.sh

@@ -4,4 +4,4 @@ set -euo pipefail
 
 # TODO: Write a command to output the names of the files in the sample-files directory whose name starts with an upper case letter.
 # Your output should contain 10 files.
-ls sample-files | grep '^[A-Z]'
+ls sample-files | grep '^[A-Z]'

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

@@ -4,4 +4,4 @@ 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]*$' | wc -l
+ls sample-files | grep '^[A-Z][^A-Z]*$' | wc -l

shell-pipelines/tr/script-01.sh

@@ -6,4 +6,4 @@ set -euo pipefail
 # The author got feedback that they're using too many exclamation marks (!).
 #
 # TODO: Write a command to output the contents of text.txt with every exclamation mark (!) replaced with a full-stop (.).
-tr '!' '.' < text.txt
+tr '!' '.' < text.txt

shell-pipelines/tr/script-02.sh

@@ -7,4 +7,4 @@ set -euo pipefail
 # so every Y should be a Z, and every Z should be a Y!
 #
 # TODO: Write a command to output the contents of text.txt with every Y and Z swapped (both upper and lower case).
-tr 'YyZz' 'ZzYy' < text.txt
+tr 'YyZz' 'ZzYy' < text.txt