From dc8dfaf5f07a1177e6d08d5bc98240d678143d80 Mon Sep 17 00:00:00 2001
From: Mohammed Abdoon <mohammedabdoon1996@gmail.com>
Date: Sat, 21 Mar 2026 22:34:12 +0000
Subject: [PATCH 1/9] ls-grep exerise

---
 shell-pipelines/ls-grep/script-01.sh | 1 +
 shell-pipelines/ls-grep/script-02.sh | 1 +
 shell-pipelines/ls-grep/script-03.sh | 1 +
 shell-pipelines/ls-grep/script-04.sh | 1 +
 4 files changed, 4 insertions(+)

diff --git a/shell-pipelines/ls-grep/script-01.sh b/shell-pipelines/ls-grep/script-01.sh
index 8c7d968a2..2530df5cf 100755
--- a/shell-pipelines/ls-grep/script-01.sh
+++ b/shell-pipelines/ls-grep/script-01.sh
@@ -4,3 +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]'
\ No newline at end of file
diff --git a/shell-pipelines/ls-grep/script-02.sh b/shell-pipelines/ls-grep/script-02.sh
index 16f5f71d9..90eb3f2bf 100755
--- a/shell-pipelines/ls-grep/script-02.sh
+++ b/shell-pipelines/ls-grep/script-02.sh
@@ -4,3 +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]'
\ No newline at end of file
diff --git a/shell-pipelines/ls-grep/script-03.sh b/shell-pipelines/ls-grep/script-03.sh
index a302ab036..5c7a491be 100755
--- a/shell-pipelines/ls-grep/script-03.sh
+++ b/shell-pipelines/ls-grep/script-03.sh
@@ -4,3 +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 and doesn't contain any other upper case letters.
 # Your output should contain 7 files.
+ls sample-files | grep '^[A-Z][a-z]*$'
diff --git a/shell-pipelines/ls-grep/script-04.sh b/shell-pipelines/ls-grep/script-04.sh
index c000b7e3b..e165a5c5f 100755
--- a/shell-pipelines/ls-grep/script-04.sh
+++ b/shell-pipelines/ls-grep/script-04.sh
@@ -4,3 +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
\ No newline at end of file

From 6ea939b167d087e24d434477924fdce3f20cf73b Mon Sep 17 00:00:00 2001
From: Mohammed Abdoon <mohammedabdoon1996@gmail.com>
Date: Sat, 21 Mar 2026 22:42:45 +0000
Subject: [PATCH 2/9] sort-uniq-head-tail exercises solved

---
 shell-pipelines/sort-uniq-head-tail/script-01.sh | 1 +
 shell-pipelines/sort-uniq-head-tail/script-02.sh | 1 +
 shell-pipelines/sort-uniq-head-tail/script-03.sh | 1 +
 shell-pipelines/sort-uniq-head-tail/script-04.sh | 1 +
 shell-pipelines/sort-uniq-head-tail/script-05.sh | 1 +
 shell-pipelines/sort-uniq-head-tail/script-06.sh | 1 +
 shell-pipelines/sort-uniq-head-tail/script-07.sh | 1 +
 7 files changed, 7 insertions(+)

diff --git a/shell-pipelines/sort-uniq-head-tail/script-01.sh b/shell-pipelines/sort-uniq-head-tail/script-01.sh
index 171e1f989..1db218dbb 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-01.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-01.sh
@@ -5,3 +5,4 @@ set -euo pipefail
 # The input for this script is the scores-table.txt file.
 # TODO: Write a command to output scores-table.txt, with lines sorted by the person's name.
 # The first line of your output should be "Ahmed London 1 10 4" (with no quotes). And the third line should be "Chandra Birmingham 12 6".
+sort scores-table.txt
\ No newline at end of file
diff --git a/shell-pipelines/sort-uniq-head-tail/script-02.sh b/shell-pipelines/sort-uniq-head-tail/script-02.sh
index 29c3c2524..f32b03b63 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-02.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-02.sh
@@ -5,3 +5,4 @@ set -euo pipefail
 # The input for this script is the scores-table.txt file.
 # TODO: Write a command to output scores-table.txt, with lines sorted by the person's first score, descending.
 # The first line of your output should be "Basia London 22 9 6" (with no quotes).
+sort -k3,3nr scores-table.txt
\ No newline at end of file
diff --git a/shell-pipelines/sort-uniq-head-tail/script-03.sh b/shell-pipelines/sort-uniq-head-tail/script-03.sh
index bcbaf3420..4b5cf8b99 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-03.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-03.sh
@@ -8,3 +8,4 @@ set -euo pipefail
 # Basia London 22 9 6
 # Piotr Glasgow 15 2 25 11 8
 # Chandra Birmingham 12 6
+sort -k3,3nr scores-table.txt | head -n 3
\ No newline at end of file
diff --git a/shell-pipelines/sort-uniq-head-tail/script-04.sh b/shell-pipelines/sort-uniq-head-tail/script-04.sh
index 65a5cfba8..02b7b95fc 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-04.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-04.sh
@@ -5,3 +5,4 @@ set -euo pipefail
 # The input for this script is the scores-table.txt file.
 # TODO: Write a command to output scores-table.txt, with shows the line for the player whose first score was the second highest.
 # Your output should be: "Piotr Glasgow 15 2 25 11 8" (without quotes).
+sort -k3,3nr scores-table.txt | head -n 2 | tail -n 1
\ No newline at end of file
diff --git a/shell-pipelines/sort-uniq-head-tail/script-05.sh b/shell-pipelines/sort-uniq-head-tail/script-05.sh
index a93cd9f9d..bdc16e1c8 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-05.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-05.sh
@@ -6,3 +6,4 @@ set -euo pipefail
 # TODO: Write a command to show a list of all events that have happened, without duplication.
 # The order they're displayed doesn't matter, but we never want to see the same event listed twice.
 # Your output should contain 6 lines.
+sort events.txt | uniq
\ No newline at end of file
diff --git a/shell-pipelines/sort-uniq-head-tail/script-06.sh b/shell-pipelines/sort-uniq-head-tail/script-06.sh
index 715c7ae5c..930f1d70c 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-06.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-06.sh
@@ -5,3 +5,4 @@ set -euo pipefail
 # The input for this script is the events.txt file.
 # TODO: Write a command to show how many times anyone has entered and exited.
 # It should be clear from your script's output that there have been 5 Entry events and 4 Exit events.
+sort events.txt | uniq -c
\ No newline at end of file
diff --git a/shell-pipelines/sort-uniq-head-tail/script-07.sh b/shell-pipelines/sort-uniq-head-tail/script-07.sh
index 7fd07e1ff..0850c7743 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-07.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-07.sh
@@ -6,3 +6,4 @@ set -euo pipefail
 # TODO: Write a command to show how many times anyone has entered and exited.
 # It should be clear from your script's output that there have been 5 Entry events and 4 Exit events.
 # The word "Event" should not appear in your script's output.
+cut -d' ' -f2 events-with-timestamps.txt | sort | uniq -c
\ No newline at end of file

From d6556ad438ef3ea0bcab868562bb40c7d37aad5b Mon Sep 17 00:00:00 2001
From: Mohammed Abdoon <mohammedabdoon1996@gmail.com>
Date: Sat, 21 Mar 2026 22:52:50 +0000
Subject: [PATCH 3/9] tr exercise

---
 shell-pipelines/tr/script-01.sh | 1 +
 shell-pipelines/tr/script-02.sh | 1 +
 2 files changed, 2 insertions(+)

diff --git a/shell-pipelines/tr/script-01.sh b/shell-pipelines/tr/script-01.sh
index 8bb0211e9..3553c5aa5 100755
--- a/shell-pipelines/tr/script-01.sh
+++ b/shell-pipelines/tr/script-01.sh
@@ -6,3 +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
\ No newline at end of file
diff --git a/shell-pipelines/tr/script-02.sh b/shell-pipelines/tr/script-02.sh
index cf3a503a2..a5250f788 100755
--- a/shell-pipelines/tr/script-02.sh
+++ b/shell-pipelines/tr/script-02.sh
@@ -7,3 +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
\ No newline at end of file

From 852b400c2ec4fc93edcbae8a456477738b3aa79c Mon Sep 17 00:00:00 2001
From: Mohammed Abdoon <mohammedabdoon1996@gmail.com>
Date: Wed, 25 Mar 2026 20:58:12 +0000
Subject: [PATCH 4/9] works with regular inputs

---
 implement-shell-tools/cat/cat.js            | 16 ++++++++++++++++
 implement-shell-tools/cat/package-lock.json | 21 +++++++++++++++++++++
 implement-shell-tools/cat/package.json      |  6 ++++++
 3 files changed, 43 insertions(+)
 create mode 100644 implement-shell-tools/cat/cat.js
 create mode 100644 implement-shell-tools/cat/package-lock.json
 create mode 100644 implement-shell-tools/cat/package.json

diff --git a/implement-shell-tools/cat/cat.js b/implement-shell-tools/cat/cat.js
new file mode 100644
index 000000000..91b05a806
--- /dev/null
+++ b/implement-shell-tools/cat/cat.js
@@ -0,0 +1,16 @@
+import { program } from "commander";
+import { promises as fs } from "node:fs";
+
+program.argument("<files...>").parse();
+
+for (const file of program.args) {
+  const stat = await fs.stat(file);
+
+  if (stat.isDirectory()) {
+    console.error(`cat: ${file}: Is a directory`);
+    continue;
+  }
+
+  const content = await fs.readFile(file, "utf-8");
+  process.stdout.write(content);
+}
diff --git a/implement-shell-tools/cat/package-lock.json b/implement-shell-tools/cat/package-lock.json
new file mode 100644
index 000000000..6179cab28
--- /dev/null
+++ b/implement-shell-tools/cat/package-lock.json
@@ -0,0 +1,21 @@
+{
+  "name": "cat",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "dependencies": {
+        "commander": "^14.0.3"
+      }
+    },
+    "node_modules/commander": {
+      "version": "14.0.3",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-14.0.3.tgz",
+      "integrity": "sha512-H+y0Jo/T1RZ9qPP4Eh1pkcQcLRglraJaSLoyOtHxu6AapkjWVCy2Sit1QQ4x3Dng8qDlSsZEet7g5Pq06MvTgw==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=20"
+      }
+    }
+  }
+}
diff --git a/implement-shell-tools/cat/package.json b/implement-shell-tools/cat/package.json
new file mode 100644
index 000000000..402b2a4e9
--- /dev/null
+++ b/implement-shell-tools/cat/package.json
@@ -0,0 +1,6 @@
+{
+  "dependencies": {
+    "commander": "^14.0.3"
+  },
+  "type": "module"
+}

From 1742e2e9953030acc4bf43b81fcd83991b8a1543 Mon Sep 17 00:00:00 2001
From: Mohammed Abdoon <mohammedabdoon1996@gmail.com>
Date: Sun, 10 May 2026 13:10:12 +0100
Subject: [PATCH 5/9] deleted unwanted files

---
 implement-shell-tools/cat/cat.js            | 16 ----------------
 implement-shell-tools/cat/package-lock.json | 21 ---------------------
 implement-shell-tools/cat/package.json      |  6 ------
 3 files changed, 43 deletions(-)
 delete mode 100644 implement-shell-tools/cat/cat.js
 delete mode 100644 implement-shell-tools/cat/package-lock.json
 delete mode 100644 implement-shell-tools/cat/package.json

diff --git a/implement-shell-tools/cat/cat.js b/implement-shell-tools/cat/cat.js
deleted file mode 100644
index 91b05a806..000000000
--- a/implement-shell-tools/cat/cat.js
+++ /dev/null
@@ -1,16 +0,0 @@
-import { program } from "commander";
-import { promises as fs } from "node:fs";
-
-program.argument("<files...>").parse();
-
-for (const file of program.args) {
-  const stat = await fs.stat(file);
-
-  if (stat.isDirectory()) {
-    console.error(`cat: ${file}: Is a directory`);
-    continue;
-  }
-
-  const content = await fs.readFile(file, "utf-8");
-  process.stdout.write(content);
-}
diff --git a/implement-shell-tools/cat/package-lock.json b/implement-shell-tools/cat/package-lock.json
deleted file mode 100644
index 6179cab28..000000000
--- a/implement-shell-tools/cat/package-lock.json
+++ /dev/null
@@ -1,21 +0,0 @@
-{
-  "name": "cat",
-  "lockfileVersion": 3,
-  "requires": true,
-  "packages": {
-    "": {
-      "dependencies": {
-        "commander": "^14.0.3"
-      }
-    },
-    "node_modules/commander": {
-      "version": "14.0.3",
-      "resolved": "https://registry.npmjs.org/commander/-/commander-14.0.3.tgz",
-      "integrity": "sha512-H+y0Jo/T1RZ9qPP4Eh1pkcQcLRglraJaSLoyOtHxu6AapkjWVCy2Sit1QQ4x3Dng8qDlSsZEet7g5Pq06MvTgw==",
-      "license": "MIT",
-      "engines": {
-        "node": ">=20"
-      }
-    }
-  }
-}
diff --git a/implement-shell-tools/cat/package.json b/implement-shell-tools/cat/package.json
deleted file mode 100644
index 402b2a4e9..000000000
--- a/implement-shell-tools/cat/package.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "dependencies": {
-    "commander": "^14.0.3"
-  },
-  "type": "module"
-}

From d3381b8b7059faf3e625fed72799a173b9776448 Mon Sep 17 00:00:00 2001
From: Mohammed Abdoon <mohammedabdoon1996@gmail.com>
Date: Sun, 10 May 2026 13:32:21 +0100
Subject: [PATCH 6/9] fixed script 6

---
 shell-pipelines/sort-uniq-head-tail/script-01.sh | 2 +-
 shell-pipelines/sort-uniq-head-tail/script-02.sh | 2 +-
 shell-pipelines/sort-uniq-head-tail/script-03.sh | 2 +-
 shell-pipelines/sort-uniq-head-tail/script-04.sh | 2 +-
 shell-pipelines/sort-uniq-head-tail/script-05.sh | 2 +-
 shell-pipelines/sort-uniq-head-tail/script-06.sh | 4 +++-
 shell-pipelines/sort-uniq-head-tail/script-07.sh | 2 +-
 7 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/shell-pipelines/sort-uniq-head-tail/script-01.sh b/shell-pipelines/sort-uniq-head-tail/script-01.sh
index 1db218dbb..845ad89da 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-01.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-01.sh
@@ -5,4 +5,4 @@ set -euo pipefail
 # The input for this script is the scores-table.txt file.
 # TODO: Write a command to output scores-table.txt, with lines sorted by the person's name.
 # The first line of your output should be "Ahmed London 1 10 4" (with no quotes). And the third line should be "Chandra Birmingham 12 6".
-sort scores-table.txt
\ No newline at end of file
+sort scores-table.txt
diff --git a/shell-pipelines/sort-uniq-head-tail/script-02.sh b/shell-pipelines/sort-uniq-head-tail/script-02.sh
index f32b03b63..e0281500d 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-02.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-02.sh
@@ -5,4 +5,4 @@ set -euo pipefail
 # The input for this script is the scores-table.txt file.
 # TODO: Write a command to output scores-table.txt, with lines sorted by the person's first score, descending.
 # The first line of your output should be "Basia London 22 9 6" (with no quotes).
-sort -k3,3nr scores-table.txt
\ No newline at end of file
+sort -k3,3nr scores-table.txt
diff --git a/shell-pipelines/sort-uniq-head-tail/script-03.sh b/shell-pipelines/sort-uniq-head-tail/script-03.sh
index 4b5cf8b99..01e6b4d0d 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-03.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-03.sh
@@ -8,4 +8,4 @@ set -euo pipefail
 # Basia London 22 9 6
 # Piotr Glasgow 15 2 25 11 8
 # Chandra Birmingham 12 6
-sort -k3,3nr scores-table.txt | head -n 3
\ No newline at end of file
+sort -k3,3nr scores-table.txt | head -n 3
diff --git a/shell-pipelines/sort-uniq-head-tail/script-04.sh b/shell-pipelines/sort-uniq-head-tail/script-04.sh
index 02b7b95fc..5603cc47d 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-04.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-04.sh
@@ -5,4 +5,4 @@ set -euo pipefail
 # The input for this script is the scores-table.txt file.
 # TODO: Write a command to output scores-table.txt, with shows the line for the player whose first score was the second highest.
 # Your output should be: "Piotr Glasgow 15 2 25 11 8" (without quotes).
-sort -k3,3nr scores-table.txt | head -n 2 | tail -n 1
\ No newline at end of file
+sort -k3,3nr scores-table.txt | head -n 2 | tail -n 1
diff --git a/shell-pipelines/sort-uniq-head-tail/script-05.sh b/shell-pipelines/sort-uniq-head-tail/script-05.sh
index bdc16e1c8..8eba57e36 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-05.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-05.sh
@@ -6,4 +6,4 @@ set -euo pipefail
 # TODO: Write a command to show a list of all events that have happened, without duplication.
 # The order they're displayed doesn't matter, but we never want to see the same event listed twice.
 # Your output should contain 6 lines.
-sort events.txt | uniq
\ No newline at end of file
+sort events.txt | uniq
diff --git a/shell-pipelines/sort-uniq-head-tail/script-06.sh b/shell-pipelines/sort-uniq-head-tail/script-06.sh
index 930f1d70c..8737dc237 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-06.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-06.sh
@@ -5,4 +5,6 @@ set -euo pipefail
 # The input for this script is the events.txt file.
 # TODO: Write a command to show how many times anyone has entered and exited.
 # It should be clear from your script's output that there have been 5 Entry events and 4 Exit events.
-sort events.txt | uniq -c
\ No newline at end of file
+
+echo "Entry: $(grep -c 'Entry' events.txt)"
+echo "Exit: $(grep -c 'Exit' events.txt)"
diff --git a/shell-pipelines/sort-uniq-head-tail/script-07.sh b/shell-pipelines/sort-uniq-head-tail/script-07.sh
index 0850c7743..0309b6c86 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-07.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-07.sh
@@ -6,4 +6,4 @@ set -euo pipefail
 # TODO: Write a command to show how many times anyone has entered and exited.
 # It should be clear from your script's output that there have been 5 Entry events and 4 Exit events.
 # The word "Event" should not appear in your script's output.
-cut -d' ' -f2 events-with-timestamps.txt | sort | uniq -c
\ No newline at end of file
+cut -d' ' -f2 events-with-timestamps.txt | sort | uniq -c

From 1cb2c0d6bf7f3c6885058ad6ea26ba9f81b5144f Mon Sep 17 00:00:00 2001
From: Mohammed Abdoon <mohammedabdoon1996@gmail.com>
Date: Sun, 10 May 2026 13:33:09 +0100
Subject: [PATCH 7/9] fixed script 7

---
 shell-pipelines/sort-uniq-head-tail/script-07.sh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/shell-pipelines/sort-uniq-head-tail/script-07.sh b/shell-pipelines/sort-uniq-head-tail/script-07.sh
index 0309b6c86..b97c1c052 100755
--- a/shell-pipelines/sort-uniq-head-tail/script-07.sh
+++ b/shell-pipelines/sort-uniq-head-tail/script-07.sh
@@ -6,4 +6,5 @@ set -euo pipefail
 # TODO: Write a command to show how many times anyone has entered and exited.
 # It should be clear from your script's output that there have been 5 Entry events and 4 Exit events.
 # The word "Event" should not appear in your script's output.
-cut -d' ' -f2 events-with-timestamps.txt | sort | uniq -c
+echo "Entry: $(grep -c 'Entry' events-with-timestamps.txt)"
+echo "Exit: $(grep -c 'Exit' events-with-timestamps.txt)"

From f9d2cd5b14a2a75e227b0beac4662816567408be Mon Sep 17 00:00:00 2001
From: Mohammed Abdoon <mohammedabdoon1996@gmail.com>
Date: Sun, 10 May 2026 13:39:02 +0100
Subject: [PATCH 8/9] fixed script 3

---
 shell-pipelines/ls-grep/script-03.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/shell-pipelines/ls-grep/script-03.sh b/shell-pipelines/ls-grep/script-03.sh
index 5c7a491be..9b79f1c8c 100755
--- a/shell-pipelines/ls-grep/script-03.sh
+++ b/shell-pipelines/ls-grep/script-03.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 and doesn't contain any other upper case letters.
 # Your output should contain 7 files.
-ls sample-files | grep '^[A-Z][a-z]*$'
+ls sample-files | grep '^[A-Z][^A-Z]*$'

From 0f2481737e9dabd6b8da25d4c3591dd0f4eebd5e Mon Sep 17 00:00:00 2001
From: Mohammed Abdoon <mohammedabdoon1996@gmail.com>
Date: Sun, 10 May 2026 13:41:53 +0100
Subject: [PATCH 9/9] added trailing lines + fixed script 4

---
 shell-pipelines/ls-grep/script-01.sh | 2 +-
 shell-pipelines/ls-grep/script-02.sh | 2 +-
 shell-pipelines/ls-grep/script-04.sh | 2 +-
 shell-pipelines/tr/script-01.sh      | 2 +-
 shell-pipelines/tr/script-02.sh      | 2 +-
 5 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/shell-pipelines/ls-grep/script-01.sh b/shell-pipelines/ls-grep/script-01.sh
index 2530df5cf..b77993b26 100755
--- a/shell-pipelines/ls-grep/script-01.sh
+++ b/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]'
\ No newline at end of file
+ls sample-files | grep '[A-Z]'
diff --git a/shell-pipelines/ls-grep/script-02.sh b/shell-pipelines/ls-grep/script-02.sh
index 90eb3f2bf..4fa4206cd 100755
--- a/shell-pipelines/ls-grep/script-02.sh
+++ b/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]'
\ No newline at end of file
+ls sample-files | grep '^[A-Z]'
diff --git a/shell-pipelines/ls-grep/script-04.sh b/shell-pipelines/ls-grep/script-04.sh
index e165a5c5f..b9b1fef9e 100755
--- a/shell-pipelines/ls-grep/script-04.sh
+++ b/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]*$' | wc -l
\ No newline at end of file
+ls sample-files | grep '^[A-Z][^A-Z]*$' | wc -l
diff --git a/shell-pipelines/tr/script-01.sh b/shell-pipelines/tr/script-01.sh
index 3553c5aa5..f91ef30d3 100755
--- a/shell-pipelines/tr/script-01.sh
+++ b/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
\ No newline at end of file
+tr '!' '.' < text.txt
diff --git a/shell-pipelines/tr/script-02.sh b/shell-pipelines/tr/script-02.sh
index a5250f788..96a208b9a 100755
--- a/shell-pipelines/tr/script-02.sh
+++ b/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
\ No newline at end of file
+tr 'YyZz' 'ZzYy' < text.txt