London | 25-SDC-July | Pezhman Azizi | Sprint 1 | Individual Shell Tools Exercises

individual-shell-tools/ls/script-01.sh

@@ -13,3 +13,4 @@ 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.
+ls 

individual-shell-tools/ls/script-02.sh

@@ -4,3 +4,4 @@ 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.
+ls child-directory

individual-shell-tools/ls/script-03.sh

@@ -5,3 +5,4 @@ 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.
+ls -R 

individual-shell-tools/ls/script-04.sh

@@ -16,8 +16,10 @@ echo "First exercise (sorted newest to oldest):"
 # TODO: Write a command which lists the files in the child-directory directory, one per line, sorted so that the most recently modified file is first.
 # The output should be a list of names in this order, one per line: helper-3.txt, helper-1.txt, helper-2.txt.
 
+ls -t1 ./child-directory
 
 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.
+ls -tr1 child-directory

jq/script-01.sh

@@ -5,3 +5,4 @@ set -euo pipefail
 # The input for this script is the person.json file.
 # TODO: Write a command to output the name of the person.
 # Your output should be exactly the string "Selma", but should not contain any quote characters.
+jq -r '.name' person.json

jq/script-02.sh

@@ -5,3 +5,5 @@ set -euo pipefail
 # The input for this script is the person.json file.
 # TODO: Write a command to output the address of the person, all on one line, with a comma between each line.
 # Your output should be exactly the string "35 Fashion Street, London, E1 6PX", but should not contain any quote characters.
+jq -r '.address | join(", ")' person.json
+

jq/script-03.sh

@@ -5,3 +5,4 @@ set -euo pipefail
 # The input for this script is the person.json file.
 # TODO: Write a command to output the name of the person, then a comma, then their profession.
 # Your output should be exactly the string "Selma, Software Engineer", but should not contain any quote characters.
+jq -r '[.name, .profession] | join(", ")' person.json

jq/script-04.sh

@@ -6,3 +6,4 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player, one per line.
 # Your output should contain 6 lines, each with just one word on it.
 # Your output should not contain any quote characters.
+jq -r '.[].name' scores.json

jq/script-05.sh

@@ -5,3 +5,4 @@ set -euo pipefail
 # The input for this script is the scores.json file.
 # 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.
+jq -r '.[] | "\(.name) \(.city)"' scores.json

jq/script-06.sh

@@ -6,3 +6,4 @@ 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" with no quotes.
+jq -r '.[] | "\(.name) \(.scores[0])"' scores.json

jq/script-07.sh

@@ -6,3 +6,4 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player along with the score from their last attempt.
 # Your output should contain 6 lines, each with one word and one number on it.
 # The first line should be "Ahmed 4" with no quotes.
+jq -r '.[] | "\(.name) \(.scores[-1])"' scores.json

jq/script-08.sh

@@ -6,3 +6,4 @@ 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" with no quotes.
+jq -r '.[] | "\(.name) \(.scores | length)"' scores.json

jq/script-09.sh

@@ -6,3 +6,4 @@ set -euo pipefail
 # TODO: Write a command to output just the names of each player along with the total scores from all of their games added together.
 # Your output should contain 6 lines, each with one word and one number on it.
 # The first line should be "Ahmed 15" with no quotes.
+jq -r '.[] | "\(.name) \(.scores | add)"' scores.json

jq/script-10.sh

@@ -5,3 +5,4 @@ set -euo pipefail
 # The input for this script is the scores.json file.
 # TODO: Write a command to output the total of adding together all players' first scores.
 # Your output should be exactly the number 54.
+jq '[.[].scores[0]] | add' scores.json

jq/script-11.sh

@@ -5,3 +5,4 @@ set -euo pipefail
 # The input for this script is the scores.json file.
 # TODO: Write a command to output the total of adding together all scores from all games from all players.
 # Your output should be exactly the number 164.
+jq '[.[].scores[]] | add' scores.json

number-systems/README.md

@@ -5,61 +5,67 @@ Do not convert any binary numbers to decimal when solving a question unless the
 The goal of these exercises is for you to gain an intuition for binary numbers. Using tools to solve the problems defeats the point.
 
 Convert the decimal number 14 to binary.
-Answer:
+Answer:  1110
 
 Convert the binary number 101101 to decimal:
-Answer:
+Answer:32,8,4,1 = 45
 
 Which is larger: 1000 or 0111?
-Answer:
+Answer: 1000 is larger since the left most digit is 1 compared to the other number.
 
 Which is larger: 00100 or 01011?
-Answer:
+Answer: 01011 is larger
 
 What is 10101 + 01010?
-Answer:
+Answer: 1111
 
 What is 10001 + 10001?
-Answer:
+Answer: 100010
 
 What's the largest number you can store with 4 bits, if you want to be able to represent the number 0?
-Answer:
+
+Answer1: If representing 0 means having 0000 AS A POSSIBLE NUMBER in the range of 0 to largest number produced by four digits, then the largest possible number is when all the digits are one which makes 1111 the largest number.
+
+Answer2: If it means having 0 in one of the digits as a possible occurrence, then the largest possible number produced when zero goes to the last digit to have the least effect which  1110 the largest number.
+
 
 How many bits would you need in order to store the numbers between 0 and 255 inclusive?
-Answer:
+Answer: since 256 is 2^8 the biggest number of digits with 255 inclusive is made when we have  digits.
 
 How many bits would you need in order to store the numbers between 0 and 3 inclusive?
-Answer:
+Answer: 2 bits
 
 How many bits would you need in order to store the numbers between 0 and 1000 inclusive?
-Answer:
+Answer: 10 bits. since 2^n - 1 = the biggest number with n bits.
 
 How can you test if a binary number is a power of two (e.g. 1, 2, 4, 8, 16, ...)?
-Answer:
+Answer: only of it has only 1 bit as 1 and the rest are zeros
 
 Convert the decimal number 14 to hex.
-Answer:
+Answer: it is E
 
 Convert the decimal number 386 to hex.
-Answer:
+Answer: 281
 
 Convert the hex number 386 to decimal.
-Answer:
+Answer:6*(16^0)+8*(16^1)+3*(16^2) = 902
 
 Convert the hex number B to decimal.
-Answer:
+Answer: 11
 
 If reading the byte 0x21 as a number, what decimal number would it mean?
-Answer:
+Answer: 21hex = 2(16^1)+1(16^0) = 33
 
 If reading the byte 0x21 as an ASCII character, what character would it mean?
-Answer:
+Answer: !
 
-If reading the byte 0x21 as a greyscale colour, as described in "Approaches for Representing Colors and Images", what colour would it mean?
-Answer:
+If reading the byte 0x21 as a gray scale colour, as described in "Approaches for Representing Colors and Images", what color would it mean?
+Answer: Since hex21 is 33 in decimal and we have a range of 0(black) to 255(white) in decimal, then 33 is relatively close to zero. So it the gray scale it a dark grey
 
 If reading the bytes 0xAA00FF as an RGB colour, as described in "Approaches for Representing Colors and Images", what colour would it mean?
-Answer:
+Answer: Each set of  2 hex digits stands for each of primary colors in the following order:
+
+RRGGBB: comparing it to AA00FF means that we don't have any greens. so we would have a mixture of blue and red. So eventually we have shade of purpule
 
 If reading the bytes 0xAA00FF as a sequence of three one-byte decimal numbers, what decimal numbers would they be?
-Answer:
+Answer: 170, 0 , 255

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]'

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]'

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]*$'

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 -c '^[A-Z][^A-Z]*$'

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

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

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

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 | sed -n '2p'

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

shell-pipelines/sort-uniq-head-tail/script-06.sh

@@ -5,3 +5,5 @@ 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.
+
+grep -oE 'Entry|Exit' events.txt | sort | uniq -c

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.
+awk '{print $3}' events-with-timestamps.txt | grep -E 'Entry|Exit' | sort | uniq -c

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 (.).
+sed 's/!/./g' text.txt

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