Sync docs (#219)

exercises/practice/darts/.docs/instructions.md

@@ -1,6 +1,6 @@
 # Instructions
 
-Write a function that returns the earned points in a single toss of a Darts game.
+Calculate the points scored in a single toss of a Darts game.
 
 [Darts][darts] is a game where players throw darts at a [target][darts-target].
 
@@ -16,7 +16,7 @@ In our particular instance of the game, the target rewards 4 different amounts o
 The outer circle has a radius of 10 units (this is equivalent to the total radius for the entire target), the middle circle a radius of 5 units, and the inner circle a radius of 1.
 Of course, they are all centered at the same point — that is, the circles are [concentric][] defined by the coordinates (0, 0).
 
-Write a function that given a point in the target (defined by its [Cartesian coordinates][cartesian-coordinates] `x` and `y`, where `x` and `y` are [real][real-numbers]), returns the correct amount earned by a dart landing at that point.
+Given a point in the target (defined by its [Cartesian coordinates][cartesian-coordinates] `x` and `y`, where `x` and `y` are [real][real-numbers]), calculate the correct score earned by a dart landing at that point.
 
 ## Credit
 

exercises/practice/darts/.meta/config.json

@@ -13,6 +13,6 @@
       ".meta/example.v"
     ]
   },
-  "blurb": "Write a function that returns the earned points in a single toss of a Darts game.",
+  "blurb": "Calculate the points scored in a single toss of a Darts game.",
   "source": "Inspired by an exercise created by a professor Della Paolera in Argentina"
 }

exercises/practice/killer-sudoku-helper/.docs/instructions.md

@@ -20,7 +20,17 @@ In a 3-digit cage with a sum of 7, there is only one valid combination: 124.
 - 1 + 2 + 4 = 7
 - Any other combination that adds up to 7, e.g. 232, would violate the rule of not repeating digits within a cage.
 
-![Sudoku grid, with three killer cages that are marked as grouped together. The first killer cage is in the 3×3 box in the top left corner of the grid. The middle column of that box forms the cage, with the followings cells from top to bottom: first cell contains a 1 and a pencil mark of 7, indicating a cage sum of 7, second cell contains a 2, third cell contains a 5. The numbers are highlighted in red to indicate a mistake. The second killer cage is in the central 3×3 box of the grid. The middle column of that box forms the cage, with the followings cells from top to bottom: first cell contains a 1 and a pencil mark of 7, indicating a cage sum of 7, second cell contains a 2, third cell contains a 4. None of the numbers in this cage are highlighted and therefore don't contain any mistakes. The third killer cage follows the outside corner of the central 3×3 box of the grid. It is made up of the following three cells: the top left cell of the cage contains a 2, highlighted in red, and a cage sum of 7. The top right cell of the cage contains a 3. The bottom right cell of the cage contains a 2, highlighted in red. All other cells are empty.][one-solution-img]
+![Sudoku grid, with three killer cages that are marked as grouped together.
+The first killer cage is in the 3×3 box in the top left corner of the grid.
+The middle column of that box forms the cage, with the followings cells from top to bottom: first cell contains a 1 and a pencil mark of 7, indicating a cage sum of 7, second cell contains a 2, third cell contains a 5.
+The numbers are highlighted in red to indicate a mistake.
+The second killer cage is in the central 3×3 box of the grid.
+The middle column of that box forms the cage, with the followings cells from top to bottom: first cell contains a 1 and a pencil mark of 7, indicating a cage sum of 7, second cell contains a 2, third cell contains a 4.
+None of the numbers in this cage are highlighted and therefore don't contain any mistakes.
+The third killer cage follows the outside corner of the central 3×3 box of the grid.
+It is made up of the following three cells: the top left cell of the cage contains a 2, highlighted in red, and a cage sum of 7.
+The top right cell of the cage contains a 3.
+The bottom right cell of the cage contains a 2, highlighted in red. All other cells are empty.][one-solution-img]
 
 ## Example 2: Cage with several combinations
 
@@ -31,7 +41,13 @@ In a 2-digit cage with a sum 10, there are 4 possible combinations:
 - 37
 - 46
 
-![Sudoku grid, all squares empty except for the middle column, column 5, which has 8 rows filled. Each continguous two rows form a killer cage and are marked as grouped together. From top to bottom: first group is a cell with value 1 and a pencil mark indicating a cage sum of 10, cell with value 9. Second group is a cell with value 2 and a pencil mark of 10, cell with value 8. Third group is a cell with value 3 and a pencil mark of 10, cell with value 7. Fourth group is a cell with value 4 and a pencil mark of 10, cell with value 6. The last cell in the column is empty.][four-solutions-img]
+![Sudoku grid, all squares empty except for the middle column, column 5, which has 8 rows filled.
+Each continguous two rows form a killer cage and are marked as grouped together.
+From top to bottom: first group is a cell with value 1 and a pencil mark indicating a cage sum of 10, cell with value 9.
+Second group is a cell with value 2 and a pencil mark of 10, cell with value 8.
+Third group is a cell with value 3 and a pencil mark of 10, cell with value 7.
+Fourth group is a cell with value 4 and a pencil mark of 10, cell with value 6.
+The last cell in the column is empty.][four-solutions-img]
 
 ## Example 3: Cage with several combinations that is restricted
 
@@ -42,7 +58,13 @@ In a 2-digit cage with a sum 10, where the column already contains a 1 and a 4,
 
 19 and 46 are not possible due to the 1 and 4 in the column according to standard Sudoku rules.
 
-![Sudoku grid, all squares empty except for the middle column, column 5, which has 8 rows filled. The first row contains a 4, the second is empty, and the third contains a 1. The 1 is highlighted in red to indicate a mistake. The last 6 rows in the column form killer cages of two cells each. From top to bottom: first group is a cell with value 2 and a pencil mark indicating a cage sum of 10, cell with value 8. Second group is a cell with value 3 and a pencil mark of 10, cell with value 7. Third group is a cell with value 1, highlighted in red, and a pencil mark of 10, cell with value 9.][not-possible-img]
+![Sudoku grid, all squares empty except for the middle column, column 5, which has 8 rows filled.
+The first row contains a 4, the second is empty, and the third contains a 1.
+The 1 is highlighted in red to indicate a mistake.
+The last 6 rows in the column form killer cages of two cells each.
+From top to bottom: first group is a cell with value 2 and a pencil mark indicating a cage sum of 10, cell with value 8.
+Second group is a cell with value 3 and a pencil mark of 10, cell with value 7.
+Third group is a cell with value 1, highlighted in red, and a pencil mark of 10, cell with value 9.][not-possible-img]
 
 ## Trying it yourself
 

exercises/practice/matching-brackets/.docs/instructions.md

@@ -1,4 +1,5 @@
 # Instructions
 
 Given a string containing brackets `[]`, braces `{}`, parentheses `()`, or any combination thereof, verify that any and all pairs are matched and nested correctly.
-The string may also contain other characters, which for the purposes of this exercise should be ignored.
+Any other characters should be ignored.
+For example, `"{what is (42)}?"` is balanced and `"[text}"` is not.

exercises/practice/matching-brackets/.docs/introduction.md

@@ -0,0 +1,8 @@
+# Introduction
+
+You're given the opportunity to write software for the Bracketeer™, an ancient but powerful mainframe.
+The software that runs on it is written in a proprietary language.
+Much of its syntax is familiar, but you notice _lots_ of brackets, braces and parentheses.
+Despite the Bracketeer™ being powerful, it lacks flexibility.
+If the source code has any unbalanced brackets, braces or parentheses, the Bracketeer™ crashes and must be rebooted.
+To avoid such a scenario, you start writing code that can verify that brackets, braces, and parentheses are balanced before attempting to run it on the Bracketeer™.

exercises/practice/parallel-letter-frequency/.docs/instructions.md

@@ -4,4 +4,4 @@ Count the frequency of letters in texts using parallel computation.
 
 Parallelism is about doing things in parallel that can also be done sequentially.
 A common example is counting the frequency of letters.
-Create a function that returns the total frequency of each letter in a list of texts and that employs parallelism.
+Employ parallelism to calculate the total frequency of each letter in a list of texts.

exercises/practice/perfect-numbers/.docs/instructions.md

@@ -2,22 +2,38 @@
 
 Determine if a number is perfect, abundant, or deficient based on Nicomachus' (60 - 120 CE) classification scheme for positive integers.
 
-The Greek mathematician [Nicomachus][nicomachus] devised a classification scheme for positive integers, identifying each as belonging uniquely to the categories of **perfect**, **abundant**, or **deficient** based on their [aliquot sum][aliquot-sum].
-The aliquot sum is defined as the sum of the factors of a number not including the number itself.
+The Greek mathematician [Nicomachus][nicomachus] devised a classification scheme for positive integers, identifying each as belonging uniquely to the categories of [perfect](#perfect), [abundant](#abundant), or [deficient](#deficient) based on their [aliquot sum][aliquot-sum].
+The _aliquot sum_ is defined as the sum of the factors of a number not including the number itself.
 For example, the aliquot sum of `15` is `1 + 3 + 5 = 9`.
 
-- **Perfect**: aliquot sum = number
-  - 6 is a perfect number because (1 + 2 + 3) = 6
-  - 28 is a perfect number because (1 + 2 + 4 + 7 + 14) = 28
-- **Abundant**: aliquot sum > number
-  - 12 is an abundant number because (1 + 2 + 3 + 4 + 6) = 16
-  - 24 is an abundant number because (1 + 2 + 3 + 4 + 6 + 8 + 12) = 36
-- **Deficient**: aliquot sum < number
-  - 8 is a deficient number because (1 + 2 + 4) = 7
-  - Prime numbers are deficient
-
-Implement a way to determine whether a given number is **perfect**.
-Depending on your language track, you may also need to implement a way to determine whether a given number is **abundant** or **deficient**.
+## Perfect
+
+A number is perfect when it equals its aliquot sum.
+For example:
+
+- `6` is a perfect number because `1 + 2 + 3 = 6`
+- `28` is a perfect number because `1 + 2 + 4 + 7 + 14 = 28`
+
+## Abundant
+
+A number is abundant when it is less than its aliquot sum.
+For example:
+
+- `12` is an abundant number because `1 + 2 + 3 + 4 + 6 = 16`
+- `24` is an abundant number because `1 + 2 + 3 + 4 + 6 + 8 + 12 = 36`
+
+## Deficient
+
+A number is deficient when it is greater than its aliquot sum.
+For example:
+
+- `8` is a deficient number because `1 + 2 + 4 = 7`
+- Prime numbers are deficient
+
+## Task
+
+Implement a way to determine whether a given number is [perfect](#perfect).
+Depending on your language track, you may also need to implement a way to determine whether a given number is [abundant](#abundant) or [deficient](#deficient).
 
 [nicomachus]: https://en.wikipedia.org/wiki/Nicomachus
 [aliquot-sum]: https://en.wikipedia.org/wiki/Aliquot_sum

exercises/practice/pig-latin/.docs/instructions.md

@@ -19,7 +19,7 @@ For example:
 
 ## Rule 2
 
-If a word begins with a one or more consonants, first move those consonants to the end of the word and then add an `"ay"` sound to the end of the word.
+If a word begins with one or more consonants, first move those consonants to the end of the word and then add an `"ay"` sound to the end of the word.
 
 For example:
 
@@ -33,7 +33,7 @@ If a word starts with zero or more consonants followed by `"qu"`, first move tho
 
 For example:
 
-- `"quick"` -> `"ickqu"` -> `"ay"` (starts with `"qu"`, no preceding consonants)
+- `"quick"` -> `"ickqu"` -> `"ickquay"` (starts with `"qu"`, no preceding consonants)
 - `"square"` -> `"aresqu"` -> `"aresquay"` (starts with one consonant followed by `"qu`")
 
 ## Rule 4

exercises/practice/queen-attack/.docs/instructions.md

@@ -8,18 +8,14 @@ A chessboard can be represented by an 8 by 8 array.
 
 So if you are told the white queen is at `c5` (zero-indexed at column 2, row 3) and the black queen at `f2` (zero-indexed at column 5, row 6), then you know that the set-up is like so:
 
-```text
-  a b c d e f g h
-8 _ _ _ _ _ _ _ _ 8
-7 _ _ _ _ _ _ _ _ 7
-6 _ _ _ _ _ _ _ _ 6
-5 _ _ W _ _ _ _ _ 5
-4 _ _ _ _ _ _ _ _ 4
-3 _ _ _ _ _ _ _ _ 3
-2 _ _ _ _ _ B _ _ 2
-1 _ _ _ _ _ _ _ _ 1
-  a b c d e f g h
-```
+![A chess board with two queens. Arrows emanating from the queen at c5 indicate possible directions of capture along file, rank and diagonal.](https://assets.exercism.org/images/exercises/queen-attack/queen-capture.svg)
 
 You are also able to answer whether the queens can attack each other.
 In this case, that answer would be yes, they can, because both pieces share a diagonal.
+
+## Credit
+
+The chessboard image was made by [habere-et-dispertire][habere-et-dispertire] using LaTeX and the [chessboard package][chessboard-package] by Ulrike Fischer.
+
+[habere-et-dispertire]: https://exercism.org/profiles/habere-et-dispertire
+[chessboard-package]: https://github.com/u-fischer/chessboard

exercises/practice/raindrops/.meta/config.json

@@ -13,7 +13,7 @@
       ".meta/example.v"
     ]
   },
-  "blurb": "Convert a number to a string, the content of which depends on the number's factors.",
+  "blurb": "Convert a number into its corresponding raindrop sounds - Pling, Plang and Plong.",
   "source": "A variation on FizzBuzz, a famous technical interview question that is intended to weed out potential candidates. That question is itself derived from Fizz Buzz, a popular children's game for teaching division.",
   "source_url": "https://en.wikipedia.org/wiki/Fizz_buzz"
 }

exercises/practice/resistor-color-duo/.docs/instructions.md

@@ -29,5 +29,5 @@ The band colors are encoded as follows:
 - White: 9
 
 From the example above:
-brown-green should return 15
+brown-green should return 15, and
 brown-green-violet should return 15 too, ignoring the third color.

exercises/practice/roman-numerals/.docs/instructions.md

@@ -1,47 +1,12 @@
-# Instructions
+# Introduction
 
-Write a function to convert from normal numbers to Roman Numerals.
+Your task is to convert a number from Arabic numerals to Roman numerals.
 
-The Romans were a clever bunch.
-They conquered most of Europe and ruled it for hundreds of years.
-They invented concrete and straight roads and even bikinis.
-One thing they never discovered though was the number zero.
-This made writing and dating extensive histories of their exploits slightly more challenging, but the system of numbers they came up with is still in use today.
-For example the BBC uses Roman numerals to date their programs.
+For this exercise, we are only concerned about traditional Roman numerals, in which the largest number is MMMCMXCIX (or 3,999).
 
-The Romans wrote numbers using letters - I, V, X, L, C, D, M; notice these letters have lots of straight lines and are hence easy to hack into stone tablets.
+~~~~exercism/note
+There are lots of different ways to convert between Arabic and Roman numerals.
+We recommend taking a naive approach first to familiarise yourself with the concept of Roman numerals and then search for more efficient methods.
 
-```text
- 1  => I
-10  => X
- 7  => VII
-```
-
-The maximum number supported by this notation is 3,999.
-
-Wikipedia says: Modern Roman numerals [...] are written by expressing each digit separately starting with the left most digit and skipping any digit with a value of zero.
-
-To see this in practice, consider the example of 1990.
-
-In Roman numerals 1990 is MCMXC:
-
-```text
- 1000 => M
-  900 => CM
-+  90 => XC
------ => -----
- 1990 => MCMXC
-```
-
-2008 is written as MMVIII:
-
-```text
- 2000 => MM
-+   8 => VIII
------ => ------
- 2008 => MMVIII
-```
-
-Learn more about [Roman numerals on Wikipedia][roman-numerals].
-
-[roman-numerals]: https://wiki.imperivm-romanvm.com/wiki/Roman_Numerals
+Make sure to check out our Deep Dive video at the end to explore the different approaches you can take!
+~~~~

exercises/practice/roman-numerals/.docs/introduction.md

@@ -0,0 +1,59 @@
+# Description
+
+Today, most people in the world use Arabic numerals (0–9).
+But if you travelled back two thousand years, you'd find that most Europeans were using Roman numerals instead.
+
+To write a Roman numeral we use the following Latin letters, each of which has a value:
+
+| M    | D   | C   | L   | X   | V   | I   |
+| ---- | --- | --- | --- | --- | --- | --- |
+| 1000 | 500 | 100 | 50  | 10  | 5   | 1   |
+
+A Roman numeral is a sequence of these letters, and its value is the sum of the letters' values.
+For example, `XVIII` has the value 18 (`10 + 5 + 1 + 1 + 1 = 18`).
+
+There's one rule that makes things trickier though, and that's that **the same letter cannot be used more than three times in succession**.
+That means that we can't express numbers such as 4 with the seemingly natural `IIII`.
+Instead, for those numbers, we use a subtraction method between two letters.
+So we think of `4` not as `1 + 1 + 1 + 1` but instead as `5 - 1`.
+And slightly confusingly to our modern thinking, we write the smaller number first.
+This applies only in the following cases: 4 (`IV`), 9 (`IX`), 40 (`XL`), 90 (`XC`), 400 (`CD`) and 900 (`CM`).
+
+Order matters in Roman numerals!
+Letters (and the special compounds above) must be ordered by decreasing value from left to right.
+
+Here are some examples:
+
+```text
+ 105 => CV
+---- => --
+ 100 => C
++  5 =>  V
+```
+
+```text
+ 106 => CVI
+---- => --
+ 100 => C
++  5 =>  V
++  1 =>   I
+```
+
+```text
+ 104 => CIV
+---- => ---
+ 100 => C
++  4 =>  IV
+```
+
+And a final more complex example:
+
+```text
+ 1996 => MCMXCVI
+----- => -------
+ 1000 => M
++ 900 =>  CM
++  90 =>    XC
++   5 =>      V
++   1 =>       I
+```

exercises/practice/roman-numerals/.meta/config.json

@@ -13,7 +13,7 @@
       ".meta/example.v"
     ]
   },
-  "blurb": "Write a function to convert from normal numbers to Roman Numerals.",
+  "blurb": "Convert modern Arabic numbers into Roman numerals.",
   "source": "The Roman Numeral Kata",
   "source_url": "https://codingdojo.org/kata/RomanNumerals/"
 }

exercises/practice/say/.docs/instructions.md

@@ -30,8 +30,6 @@ Implement breaking a number up into chunks of thousands.
 
 So `1234567890` should yield a list like 1, 234, 567, and 890, while the far simpler `1000` should yield just 1 and 0.
 
-The program must also report any values that are out of range.
-
 ## Step 3
 
 Now handle inserting the appropriate scale word between those chunks.

exercises/practice/space-age/.docs/instructions.md

@@ -1,25 +1,28 @@
 # Instructions
 
-Given an age in seconds, calculate how old someone would be on:
+Given an age in seconds, calculate how old someone would be on a planet in our Solar System.
 
-- Mercury: orbital period 0.2408467 Earth years
-- Venus: orbital period 0.61519726 Earth years
-- Earth: orbital period 1.0 Earth years, 365.25 Earth days, or 31557600 seconds
-- Mars: orbital period 1.8808158 Earth years
-- Jupiter: orbital period 11.862615 Earth years
-- Saturn: orbital period 29.447498 Earth years
-- Uranus: orbital period 84.016846 Earth years
-- Neptune: orbital period 164.79132 Earth years
+One Earth year equals 365.25 Earth days, or 31,557,600 seconds.
+If you were told someone was 1,000,000,000 seconds old, their age would be 31.69 Earth-years.
 
-So if you were told someone were 1,000,000,000 seconds old, you should
-be able to say that they're 31.69 Earth-years old.
+For the other planets, you have to account for their orbital period in Earth Years:
 
-If you're wondering why Pluto didn't make the cut, go watch [this YouTube video][pluto-video].
+| Planet  | Orbital period in Earth Years |
+| ------- | ----------------------------- |
+| Mercury | 0.2408467                     |
+| Venus   | 0.61519726                    |
+| Earth   | 1.0                           |
+| Mars    | 1.8808158                     |
+| Jupiter | 11.862615                     |
+| Saturn  | 29.447498                     |
+| Uranus  | 84.016846                     |
+| Neptune | 164.79132                     |
 
-Note: The actual length of one complete orbit of the Earth around the sun is closer to 365.256 days (1 sidereal year).
+~~~~exercism/note
+The actual length of one complete orbit of the Earth around the sun is closer to 365.256 days (1 sidereal year).
 The Gregorian calendar has, on average, 365.2425 days.
 While not entirely accurate, 365.25 is the value used in this exercise.
 See [Year on Wikipedia][year] for more ways to measure a year.
 
-[pluto-video]: https://www.youtube.com/watch?v=Z_2gbGXzFbs
 [year]: https://en.wikipedia.org/wiki/Year#Summary
+~~~~