LONDON SDC | Pooriya Ketabi | Module-Tools | Sprint-1 | Number systems exercises

individual-shell-tools/awk/1

@@ -0,0 +1 @@
+15

individual-shell-tools/awk/17

@@ -0,0 +1 @@
+25

individual-shell-tools/awk/4

@@ -0,0 +1 @@
+19

individual-shell-tools/awk/5

@@ -0,0 +1,6 @@
+19
+19
+25
+15
+26
+23

individual-shell-tools/awk/6

@@ -0,0 +1,2 @@
+19
+23

individual-shell-tools/awk/8

@@ -0,0 +1 @@
+26

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

@@ -4,3 +4,5 @@ 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

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

@@ -4,3 +4,5 @@ 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

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

@@ -5,3 +5,5 @@ 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

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

@@ -5,3 +5,5 @@ 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

individual-shell-tools/awk/script-05.sh

@@ -5,3 +5,9 @@ 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 '{sum += length($3) < $NF} END {print sum}{print $1}' ./scores-table.txt
+
+# awk 'BEGIN{print $1} CONDITION{sum += length($3) < $NF} END{print sum}' ./scores-table.txt
+
+awk '{print $1, NF-2}' ./scores-table.txt

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

@@ -1,6 +1,5 @@
-#!/bin/bash
-
 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

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

@@ -11,3 +11,5 @@ 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/*

individual-shell-tools/cat/script-04-stretch.sh

@@ -13,3 +13,5 @@ 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 ../helper-files/* | nl

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

@@ -4,3 +4,5 @@ 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

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

@@ -4,3 +4,5 @@ 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 -i "Doctor" dialogue.txt

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

@@ -4,3 +4,5 @@ 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

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

@@ -4,3 +4,4 @@ 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

individual-shell-tools/grep/script-05.sh

@@ -4,3 +4,4 @@ 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 -B1 "cure" ./dialogue.txt

individual-shell-tools/grep/script-06.sh

@@ -4,3 +4,4 @@ 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

individual-shell-tools/grep/script-07.sh

@@ -4,3 +4,5 @@ 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

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

@@ -13,3 +13,5 @@ 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-03.sh

@@ -5,3 +5,5 @@ 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 +16,9 @@ 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
 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

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

@@ -5,3 +5,5 @@ 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.".
+
+sed s/i/I/g ./input.txt

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

@@ -5,3 +5,4 @@ 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".
+sed s/[0-9]//g ./input.txt

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

@@ -4,3 +4,6 @@ set -euo pipefail
 
 # TODO: Write a command to output input.txt removing any line which contains a number.
 # The output should contain 6 lines.
+
+# sed -n s/[0-9]*//gp ./input.txt
+sed /[0-9]/d ./input.txt

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

@@ -4,3 +4,5 @@ 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.
+
+sed "s/We'll/We will/" input.txt

individual-shell-tools/sed/script-05.sh

@@ -6,3 +6,5 @@ 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.
+
+sed -E 's/^([0-9]+) (.+)$/\2 \1/' input.txt

individual-shell-tools/sed/script-06.sh

@@ -8,3 +8,5 @@ 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.".
+
+sed 's/,\([^[:space:]]\)/, \1/g' input.txt

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

@@ -4,3 +4,5 @@ set -euo pipefail
 
 # TODO: Write a command to output the number of words in the file helper-files/helper-3.txt.
 # The output should include the number 19. The output should not include the number 92.
+
+wc -w ../helper-files/helper-3.txt

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

@@ -8,3 +8,6 @@ set -euo pipefail
 #        1       7      39 ../helper-files/helper-2.txt
 #        3      19      92 ../helper-files/helper-3.txt
 #        5      30     151 total
+
+wc ../helper-files/*
+# wc -lwc ../helper-files/helper-1.txt ../helper-files/helper-2.txt ../helper-files/helper-3.txt

number-systems/README.md

@@ -5,61 +5,74 @@ 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**
+                AND
+            It can be **-19** as well, 010011 => 16+2+1 = 19 but negative
 
 Which is larger: 1000 or 0111?
-Answer:
+    Answer: If consider as **UNsigned** binary: **1000** as 8 > 7 
+                OR
+            If consider as **Signed** binary: **0111** as 7 > -8 0111 + 1 = 1000 => -8
 
 Which is larger: 00100 or 01011?
-Answer:
+    Answer: **01011**
 
 What is 10101 + 01010?
-Answer:
+    Answer: **11111**
 
 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:
+    Answer: **15**
 
 How many bits would you need in order to store the numbers between 0 and 255 inclusive?
-Answer:
+    Answer: **8 bits**
 
 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: `2^n - 1` => 2^10 - 1 = 1023 => **10 bits**
 
 How can you test if a binary number is a power of two (e.g. 1, 2, 4, 8, 16, ...)?
-Answer:
+    Answer: I can check if the binary number include **ONLY one "1"**, it`s a power of two, since each bit represent a power two.
+            **But I don`t know what you mean by the word "test" here**
 
 Convert the decimal number 14 to hex.
-Answer:
+    Answer: **E**
 
 Convert the decimal number 386 to hex.
-Answer:
+    Answer: 386/16 = 24 and 2 remainder
+            24/16  = 1  and 8 remainder
+            1/16 = 0    and 1 remainder
+            So **182**
 
 Convert the hex number 386 to decimal.
-Answer:
+    Answer: 16^2 * 3 = 768
+            16^1 * 8 = 128 
+            16^0 * 6 = 6
+            So **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: **33**
 
 If reading the byte 0x21 as an ASCII character, what character would it mean?
-Answer:
+    Answer: According to `ASCII table` it`s **!**
 
 If reading the byte 0x21 as a greyscale colour, as described in "Approaches for Representing Colors and Images", what colour would it mean?
-Answer:
+    Answer: Since greyscale colour range can be from `0 (black) to 255 (white)`, and `0x21 = 0d33`, So it means **Very Dark Gray close to Black**
 
 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: Since we got `AA = 170 Red`, `00 = no Green`, `FF = 255 Blue`, it representing **Dark Blue close to Purple**
 
 If reading the bytes 0xAA00FF as a sequence of three one-byte decimal numbers, what decimal numbers would they be?
-Answer:
+    Answer: 1st byte `AA` = **170**
+            2nd byte `00` = **0**
+            3rd byte `FF` = **255**