CodeYourFuture · juneMonton · Mar 24, 2026 · Mar 24, 2026 · Mar 25, 2026 · Mar 25, 2026
diff --git a/individual-shell-tools/awk/script-01.sh b/individual-shell-tools/awk/script-01.sh
@@ -4,3 +4,10 @@ set -euo pipefail
 
 # TODO: Write a command to output just the names of each player in `scores-table.txt`.
 # Your output should contain 6 lines, each with just one word on it.
+
+awk '{print $1}' scores-table.txt
+
+# **How it works:**
+# - `awk` processes the file line by line
+# - `$1` refers to the first field (column) on each line, which is the player's name
+# - This gives you 6 lines, one name each
diff --git a/individual-shell-tools/awk/script-02.sh b/individual-shell-tools/awk/script-02.sh
@@ -4,3 +4,13 @@ set -euo pipefail
 
 # TODO: Write a command to output the names of each player, as well as their city.
 # Your output should contain 6 lines, each with two words on it, separated by a space.
+
+awk '{print $1, $2}' scores-table.txt
+
+# **How it works:**
+# - `$1` = player name
+# - `$2` = city
+# - The `,` between them prints a **space** between the two values
+
+#or you can also use,
+#cut -d' ' -f1,2 scores-table.txt
diff --git a/individual-shell-tools/awk/script-03.sh b/individual-shell-tools/awk/script-03.sh
@@ -5,3 +5,11 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player along with the score from their first attempt.
 # Your output should contain 6 lines, each with one word and one number on it.
 # The first line should be "Ahmed 1".
+
+awk '{print $1, $3}' scores-table.txt
+
+#how it works
+#awk sees each word/number separated by spaces as a numbered field:
+#awk reads the file line by line
+# For each line, {print $1, $3} prints the 1st and 3rd fields
+# The , between $1 and $3 adds a space between them
diff --git a/individual-shell-tools/awk/script-04.sh b/individual-shell-tools/awk/script-04.sh
@@ -5,3 +5,12 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player in London along with the score from their last attempt.
 # Your output should contain 3 lines, each with one word and one number on it.
 # The first line should be "Ahmed 4".
+
+awk '$2 == "London" {print $1, $NF}' scores-table.txt
+
+# awk goes line by line and does two things:
+
+# Filter — $2 == "London" skips any line where the 2nd field isn't London
+# Print — for matching lines, print the name ($1) and the last score ($NF)
+
+# $NF is the smart part — it automatically counts the fields on each line and picks the last one, so it doesn't matter that Leila has fewer scores than the others.
diff --git a/individual-shell-tools/awk/script-05.sh b/individual-shell-tools/awk/script-05.sh
@@ -5,3 +5,10 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player along with the number of times they've played the game.
 # Your output should contain 6 lines, each with one word and one number on it.
 # The first line should be "Ahmed 3".
+
+awk '{print $1, NF-2}' scores-table.txt
+
+# awk goes line by line and does two things:
+
+# Print the name — $1 grabs the first field
+# Count the scores — NF is the total number of fields, minus 2 removes the name and city, leaving just the number of scores
diff --git a/individual-shell-tools/awk/script-06-stretch.sh b/individual-shell-tools/awk/script-06-stretch.sh
@@ -6,3 +6,13 @@ set -euo pipefail
 
 # TODO: Write a command to output the total of adding together all players' first scores.
 # Your output should be exactly the number 54.
+
+
+awk '{sum += $3} END {print sum}' scores-table.txt
+
+# awk does two things:
+
+# sum += $3 — goes line by line, continuously adding each player's first score ($3) to a running total
+# END {print sum} — once all lines are done, prints the final total
+
+# END is the key new concept — it's a special block that runs once after all lines have been read.
diff --git a/individual-shell-tools/awk/script-07-stretch.sh b/individual-shell-tools/awk/script-07-stretch.sh
@@ -7,3 +7,13 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player along with the total of adding all of that player's scores.
 # Your output should contain 6 lines, each with one word and one number on it.
 # The first line should be "Ahmed 15". The second line should be "Basia 37"
+
+
+awk '{sum=0; for(i=3; i<=NF; i++) sum+=$i; print $1, sum}' scores-table.txt
+
+# **How it works:**
+
+# 1. **`sum=0`** — resets the total for each new player/line
+# 2. **`for(i=3; i<=NF; i++)`** — loops through fields starting from `$3` (first score) up to `$NF` (last score), skipping name and city
+# 3. **`sum+=$i`** — adds each score to the total
+# 4. **`print $1, sum`** — prints the player name and their total
diff --git a/individual-shell-tools/cat/script-01.sh b/individual-shell-tools/cat/script-01.sh
@@ -4,3 +4,10 @@ set -euo pipefail
 
 # TODO: Write a command to output the contents of the helper-1.txt file inside the helper-files directory to the terminal.
 # The output of this command should be "Once upon a time...".
+
+cat ../helper-files/helper-1.txt
+
+
+
+# cat reads a file and prints its contents to the terminal
+# helper-files/helper-1.txt is the relative path — it looks for a folder called helper-files in your current directory, then the file inside it
diff --git a/individual-shell-tools/cat/script-02.sh b/individual-shell-tools/cat/script-02.sh
@@ -11,3 +11,11 @@ set -euo pipefail
 # It looked delicious.
 # I was tempted to take a bite of it.
 # But this seemed like a bad idea...
+
+
+cat ../helper-files/*
+
+# * is a wildcard that matches all files inside the helper-files directory
+# So cat helper-files/* expands to all files at once, letting you call cat just once
+# cat then prints them all in alphabetical file order
+
diff --git a/individual-shell-tools/cat/script-03.sh b/individual-shell-tools/cat/script-03.sh
@@ -9,3 +9,9 @@ set -euo pipefail
 # 1 It looked delicious.
 # 2 I was tempted to take a bite of it.
 # 3 But this seemed like a bad idea...
+
+cat -n ../helper-files/helper-3.txt
+
+# How it works:
+
+# cat -n is the same cat command but the -n flag adds line numbers to the output
diff --git a/individual-shell-tools/cat/script-04-stretch.sh b/individual-shell-tools/cat/script-04-stretch.sh
@@ -13,3 +13,10 @@ set -euo pipefail
 # 3 It looked delicious.
 # 4 I was tempted to take a bite of it.
 # 5 But this seemed like a bad idea...
+
+cat -n ../helper-files/*
+
+# How it works:
+
+# cat -n with multiple files normally resets line numbers per file
+# But with * wildcard, cat treats all files as one continuous stream, so line numbers keep incrementing across all files
diff --git a/individual-shell-tools/grep/script-01.sh b/individual-shell-tools/grep/script-01.sh
@@ -4,3 +4,10 @@ set -euo pipefail
 
 # TODO: Write a command to output every line in dialogue.txt said by the Doctor.
 # The output should contain 6 lines.
+
+grep "^Doctor:" dialogue.txt
+
+# grep — scans files and returns lines that match a pattern
+# -c — instead of printing matching lines, prints the count of matches per file
+# ^Doctor: — the pattern; ^ means start of line, so only matches lines where Doctor: is at the beginning
+# *.txt — runs across all .txt files in the current directory
diff --git a/individual-shell-tools/grep/script-02.sh b/individual-shell-tools/grep/script-02.sh
@@ -4,3 +4,13 @@ set -euo pipefail
 
 # TODO: Write a command to output every line in dialogue.txt that contains the word Doctor (regardless of case).
 # The output should contain 9 lines.
+
+grep -in "Doctor" dialogue.txt
+
+# How it works:
+
+# grep — scans files and returns lines that match a pattern
+# -i — makes the search case-insensitive, matching Doctor, doctor, DOCTOR etc.
+# -n — shows the line number of each matching line
+# "Doctor" — the pattern to search for
+# dialogue.txt — the file to search in
diff --git a/individual-shell-tools/grep/script-03.sh b/individual-shell-tools/grep/script-03.sh
@@ -4,3 +4,10 @@ set -euo pipefail
 
 # TODO: Write a command to output the number of lines in dialogue.txt that contain the word Doctor (regardless of case).
 # The output should be exactly the number 9.
+
+grep -ic "Doctor" dialogue.txt
+
+# How it works:
+
+# -i makes the search case-insensitive
+# -c instead of printing the matching lines, it prints the count of matching lines
diff --git a/individual-shell-tools/grep/script-04.sh b/individual-shell-tools/grep/script-04.sh
@@ -4,3 +4,10 @@ set -euo pipefail
 
 # TODO: Write a command to output every line in dialogue.txt that does not contain the word "Hello" (regardless of case).
 # The output should contain 10 lines.
+
+grep -iv "Hello" dialogue.txt
+
+# How it works:
+
+# -i makes the search case-insensitive
+# -v inverts the match — prints every line that does not contain the word "Hello"
diff --git a/individual-shell-tools/grep/script-05.sh b/individual-shell-tools/grep/script-05.sh
@@ -4,3 +4,12 @@ set -euo pipefail
 
 # TODO: Write a command to output every line in dialogue.txt that contains the string "cure", as well as the line before that line.
 # The output should contain two pairs of two lines of text (with a separator between them).
+
+
+grep -iB1 "cure" dialogue.txt
+
+# How it works:
+
+# -i makes the search case-insensitive
+# -B1 prints 1 line Before each matching line
+# The separator -- is automatically added by grep between each pair of results
diff --git a/individual-shell-tools/grep/script-06.sh b/individual-shell-tools/grep/script-06.sh
@@ -4,3 +4,10 @@ set -euo pipefail
 
 # TODO: Write a command to output the name of every `.txt` file in this directory which contains a line of dialogue said by the Doctor.
 # The output should contain two filenames.
+
+grep -l "Doctor" *.txt
+
+# How it works:
+
+# -l instead of printing the matching lines, it prints only the filename of each file that contains a match
+# *.txt searches through all .txt files in the current directory
diff --git a/individual-shell-tools/grep/script-07.sh b/individual-shell-tools/grep/script-07.sh
@@ -4,3 +4,12 @@ set -euo pipefail
 
 # TODO: Write a command to output, for each `.txt` file in this directory, how many lines of dialogue the Doctor has.
 # The output should show that dialogue.txt contains 6 lines, dialogue-2.txt contains 2, and dialogue-3.txt contains 0.
+
+
+grep -c "^Doctor" *.txt
+
+# How it works:
+
+# ^Doctor — ^ means "start of line", so it only matches lines where Doctor appears at the beginning, filtering out lines where Doctor is just mentioned mid-sentence
+# -c — prints the count of matching lines per file
+# *.txt — runs across all .txt files in the current directory
diff --git a/individual-shell-tools/ls/script-01.sh b/individual-shell-tools/ls/script-01.sh
@@ -13,3 +13,8 @@ fi
 
 # TODO: Write a command to list the files and folders in this directory.
 # The output should be a list of names including child-directory, script-01.sh, script-02.sh, and more.
+
+
+#-------answer--------------
+
+# ls
diff --git a/individual-shell-tools/ls/script-02.sh b/individual-shell-tools/ls/script-02.sh
@@ -4,3 +4,10 @@ set -euo pipefail
 
 # TODO: Write a command which lists all of the files in the directory named child-directory.
 # The output should be a list of names: helper-1.txt, helper-2.txt, helper-3.txt.
+
+#-------answer--------------
+
+ls child-directory
+
+# ls — lists files and folders
+# child-directory — the folder to look inside
diff --git a/individual-shell-tools/ls/script-03.sh b/individual-shell-tools/ls/script-03.sh
@@ -5,3 +5,10 @@ set -euo pipefail
 # TODO: Write a command which _recursively_ lists all of the files and folders in this directory _and_ all of the files inside those folders.
 # The output should be a list of names including: child-directory, script-01.sh, helper-1.txt (and more).
 # The formatting of the output doesn't matter.
+
+#-------answer--------------
+
+ls -R
+
+# ls — lists files and folders
+# -R — recursively lists all files and folders inside every subdirectory too
diff --git a/individual-shell-tools/ls/script-04.sh b/individual-shell-tools/ls/script-04.sh
@@ -21,3 +21,19 @@ echo "Second exercise (sorted oldest to newest):"
 
 # TODO: Write a command which does the same as above, but sorted in the opposite order (oldest first).
 # The output should be a list of names in this order, one per line: helper-2.txt, helper-1.txt, helper-3.txt.
+
+
+#-------------answer--------------
+
+# First exercise (sorted newest to oldest):
+ls -t1 child-directory
+
+# Second exercise (sorted oldest to newest):
+ls -tr1 child-directory
+
+# How it works:
+
+# -t — sorts by modification time, newest first
+# -r — reverses the order, making it oldest first
+# -1 — displays one file per line
+# child-directory — the folder to list
diff --git a/individual-shell-tools/sed/script-01.sh b/individual-shell-tools/sed/script-01.sh
@@ -5,3 +5,18 @@ set -euo pipefail
 # TODO: Write a command to output input.txt with all occurrences of the letter `i` replaced with `I`.
 # The output should contain 11 lines.
 # The first line of the output should be: "ThIs Is a sample fIle for experImentIng wIth sed.".
+
+
+#---------------answer--------------
+
+sed 's/i/I/g' input.txt
+
+# How it works:
+
+# sed — stream editor that transforms text
+# s/i/I/g — the substitution command:
+
+# s — substitute
+# i — the pattern to find
+# I — the replacement
+# g — globally replace all occurrences on each line, not just the first
diff --git a/individual-shell-tools/sed/script-02.sh b/individual-shell-tools/sed/script-02.sh
@@ -5,3 +5,15 @@ set -euo pipefail
 # TODO: Write a command to output input.txt with numbers removed.
 # The output should contain 11 lines.
 # Line 6 of the output should be " Alisha".
+
+#---------------answer--------------
+
+sed 's/[0-9]//g' input.txt
+
+# How it works:
+
+# s/[0-9]//g — the substitution command:
+
+# [0-9] — matches any digit (0 through 9)
+# `` — replaces with nothing (deletes it)
+# g — removes all occurrences on each line
diff --git a/individual-shell-tools/sed/script-03.sh b/individual-shell-tools/sed/script-03.sh
@@ -4,3 +4,13 @@ set -euo pipefail
 
 # TODO: Write a command to output input.txt removing any line which contains a number.
 # The output should contain 6 lines.
+
+
+#---------------answer--------------
+
+sed '/[0-9]/d' input.txt
+
+# How it works:
+
+# /[0-9]/ — matches any line containing a digit
+# d — deletes the matching lines from the output
diff --git a/individual-shell-tools/sed/script-04.sh b/individual-shell-tools/sed/script-04.sh
@@ -4,3 +4,14 @@ set -euo pipefail
 
 # TODO: Write a command to output input.txt replacing every occurrence of the string "We'll" with "We will".
 # The output should contain 11 lines.
+
+
+#---------------answer--------------
+
+sed "s/We'll/We will/g" input.txt
+
+# How it works:
+
+# sed — stream editor that transforms text line by line
+# s/We'll/We will/g — substitute We'll with We will on every occurrence
+# double quotes — used instead of single quotes because the pattern contains a '
diff --git a/individual-shell-tools/sed/script-05.sh b/individual-shell-tools/sed/script-05.sh
@@ -6,3 +6,17 @@ set -euo pipefail
 # If a line starts with a number and a space, make the line instead end with a space and the number.
 # So line 6 which currently reads "37 Alisha" should instead read "Alisha 37".
 # The output should contain 11 lines.
+
+
+#---------------answer--------------
+
+sed 's/^\([0-9]*\) \(.*\)/\2 \1/' input.txt
+
+# How it works:
+
+# sed — stream editor that transforms text line by line
+# ^ — matches the start of the line
+# \([0-9]*\) — captures the number as group 1
+#   — matches the space between number and name
+# \(.*\) — captures the rest of the line as group 2
+# \2 \1 — prints group 2 (name) first, then group 1 (number), swapping them
diff --git a/individual-shell-tools/sed/script-06.sh b/individual-shell-tools/sed/script-06.sh
@@ -8,3 +8,16 @@ set -euo pipefail
 # The output should contain 11 lines.
 # Line 3 should be "It contains many lines, and there are some things you may want to do with each of them.".
 # Line 11 should be "We also should remember, when we go shopping, to get 4 items: oranges, cheese, bread, olives.".
+
+
+#---------------answer--------------
+
+sed 's/,\([^ ]\)/, \1/g' input.txt
+
+# How it works:
+
+# sed — stream editor that transforms text line by line
+# , — matches a comma
+# \([^ ]\) — captures any character that is not a space after the comma as group 1
+# , \1 — replaces with a comma, a space, then group 1
+# g — applies to all occurrences on each line