sync exercise docs

exercises/practice/acronym/.docs/instructions.md

@@ -10,8 +10,8 @@ Punctuation is handled as follows: hyphens are word separators (like whitespace)
 
 For example:
 
-|Input|Output|
-|-|-|
-|As Soon As Possible|ASAP|
-|Liquid-crystal display|LCD|
-|Thank George It's Friday!|TGIF|
+| Input                     | Output |
+| ------------------------- | ------ |
+| As Soon As Possible       | ASAP   |
+| Liquid-crystal display    | LCD    |
+| Thank George It's Friday! | TGIF   |

exercises/practice/affine-cipher/.docs/instructions.md

@@ -6,7 +6,7 @@ The affine cipher is a type of monoalphabetic substitution cipher.
 Each character is mapped to its numeric equivalent, encrypted with a mathematical function and then converted to the letter relating to its new numeric value.
 Although all monoalphabetic ciphers are weak, the affine cipher is much stronger than the atbash cipher, because it has many more keys.
 
-[//]: # ( monoalphabetic as spelled by Merriam-Webster, compare to polyalphabetic )
+[//]: # " monoalphabetic as spelled by Merriam-Webster, compare to polyalphabetic "
 
 ## Encryption
 
@@ -23,7 +23,7 @@ Where:
   For the Roman alphabet `m` is `26`.
 - `a` and `b` are integers which make the encryption key
 
-Values `a` and `m` must be *coprime* (or, *relatively prime*) for automatic decryption to succeed, i.e., they have number `1` as their only common factor (more information can be found in the [Wikipedia article about coprime integers][coprime-integers]).
+Values `a` and `m` must be _coprime_ (or, _relatively prime_) for automatic decryption to succeed, i.e., they have number `1` as their only common factor (more information can be found in the [Wikipedia article about coprime integers][coprime-integers]).
 In case `a` is not coprime to `m`, your program should indicate that this is an error.
 Otherwise it should encrypt or decrypt with the provided key.
 

exercises/practice/all-your-base/.docs/instructions.md

@@ -14,20 +14,20 @@ Given a number in base **a**, represented as a sequence of digits, convert it to
 
 In positional notation, a number in base **b** can be understood as a linear combination of powers of **b**.
 
-The number 42, *in base 10*, means:
+The number 42, _in base 10_, means:
 
 `(4 * 10^1) + (2 * 10^0)`
 
-The number 101010, *in base 2*, means:
+The number 101010, _in base 2_, means:
 
 `(1 * 2^5) + (0 * 2^4) + (1 * 2^3) + (0 * 2^2) + (1 * 2^1) + (0 * 2^0)`
 
-The number 1120, *in base 3*, means:
+The number 1120, _in base 3_, means:
 
 `(1 * 3^3) + (1 * 3^2) + (2 * 3^1) + (0 * 3^0)`
 
 I think you got the idea!
 
-*Yes. Those three numbers above are exactly the same. Congratulations!*
+_Yes. Those three numbers above are exactly the same. Congratulations!_
 
 [positional-notation]: https://en.wikipedia.org/wiki/Positional_notation

exercises/practice/allergies/.docs/instructions.md

@@ -22,6 +22,6 @@ Now, given just that score of 34, your program should be able to say:
 - Whether Tom is allergic to any one of those allergens listed above.
 - All the allergens Tom is allergic to.
 
-Note: a given score may include allergens **not** listed above (i.e.  allergens that score 256, 512, 1024, etc.).
+Note: a given score may include allergens **not** listed above (i.e. allergens that score 256, 512, 1024, etc.).
 Your program should ignore those components of the score.
 For example, if the allergy score is 257, your program should only report the eggs (1) allergy.

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

@@ -5,9 +5,9 @@ An [Armstrong number][armstrong-number] is a number that is the sum of its own d
 For example:
 
 - 9 is an Armstrong number, because `9 = 9^1 = 9`
-- 10 is *not* an Armstrong number, because `10 != 1^2 + 0^2 = 1`
+- 10 is _not_ an Armstrong number, because `10 != 1^2 + 0^2 = 1`
 - 153 is an Armstrong number, because: `153 = 1^3 + 5^3 + 3^3 = 1 + 125 + 27 = 153`
-- 154 is *not* an Armstrong number, because: `154 != 1^3 + 5^3 + 4^3 = 1 + 125 + 64 = 190`
+- 154 is _not_ an Armstrong number, because: `154 != 1^3 + 5^3 + 4^3 = 1 + 125 + 64 = 190`
 
 Write some code to determine whether a number is an Armstrong number.
 

exercises/practice/binary-search/.docs/instructions.md

@@ -11,7 +11,7 @@ Binary search only works when a list has been sorted.
 
 The algorithm looks like this:
 
-- Find the middle element of a *sorted* list and compare it with the item we're looking for.
+- Find the middle element of a _sorted_ list and compare it with the item we're looking for.
 - If the middle element is our item, then we're done!
 - If the middle element is greater than our item, we can eliminate that element and all the elements **after** it.
 - If the middle element is less than our item, we can eliminate that element and all the elements **before** it.

exercises/practice/book-store/.docs/instructions.md

@@ -1,6 +1,6 @@
 # Instructions
 
-To try and encourage more sales of different books from a popular 5 books series, a bookshop has decided to offer discounts on multiple book purchases.
+To try and encourage more sales of different books from a popular 5 book series, a bookshop has decided to offer discounts on multiple book purchases.
 
 One copy of any of the five books costs $8.
 

exercises/practice/circular-buffer/.docs/instructions.md

@@ -4,39 +4,55 @@ A circular buffer, cyclic buffer or ring buffer is a data structure that uses a
 
 A circular buffer first starts empty and of some predefined length.
 For example, this is a 7-element buffer:
-<!-- prettier-ignore -->
-    [ ][ ][ ][ ][ ][ ][ ]
+
+```text
+[ ][ ][ ][ ][ ][ ][ ]
+```
 
 Assume that a 1 is written into the middle of the buffer (exact starting location does not matter in a circular buffer):
-<!-- prettier-ignore -->
-    [ ][ ][ ][1][ ][ ][ ]
+
+```text
+[ ][ ][ ][1][ ][ ][ ]
+```
 
 Then assume that two more elements are added — 2 & 3 — which get appended after the 1:
-<!-- prettier-ignore -->
-    [ ][ ][ ][1][2][3][ ]
+
+```text
+[ ][ ][ ][1][2][3][ ]
+```
 
 If two elements are then removed from the buffer, the oldest values inside the buffer are removed.
 The two elements removed, in this case, are 1 & 2, leaving the buffer with just a 3:
-<!-- prettier-ignore -->
-    [ ][ ][ ][ ][ ][3][ ]
+
+```text
+[ ][ ][ ][ ][ ][3][ ]
+```
 
 If the buffer has 7 elements then it is completely full:
-<!-- prettier-ignore -->
-    [5][6][7][8][9][3][4]
+
+```text
+[5][6][7][8][9][3][4]
+```
 
 When the buffer is full an error will be raised, alerting the client that further writes are blocked until a slot becomes free.
 
 When the buffer is full, the client can opt to overwrite the oldest data with a forced write.
 In this case, two more elements — A & B — are added and they overwrite the 3 & 4:
-<!-- prettier-ignore -->
-    [5][6][7][8][9][A][B]
+
+```text
+[5][6][7][8][9][A][B]
+```
 
 3 & 4 have been replaced by A & B making 5 now the oldest data in the buffer.
 Finally, if two elements are removed then what would be returned is 5 & 6 yielding the buffer:
-<!-- prettier-ignore -->
-    [ ][ ][7][8][9][A][B]
+
+```text
+[ ][ ][7][8][9][A][B]
+```
 
 Because there is space available, if the client again uses overwrite to store C & D then the space where 5 & 6 were stored previously will be used not the location of 7 & 8.
 7 is still the oldest element and the buffer is once again full.
-<!-- prettier-ignore -->
-    [C][D][7][8][9][A][B]
+
+```text
+[C][D][7][8][9][A][B]
+```

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

@@ -6,6 +6,8 @@ Write a function that returns the earned points in a single toss of a Darts game
 
 In our particular instance of the game, the target rewards 4 different amounts of points, depending on where the dart lands:
 
+![Our dart scoreboard with values from a complete miss to a bullseye](https://assets.exercism.org/images/exercises/darts/darts-scoreboard.svg)
+
 - If the dart lands outside the target, player earns no points (0 points).
 - If the dart lands in the outer circle of the target, player earns 1 point.
 - If the dart lands in the middle circle of the target, player earns 5 points.
@@ -16,8 +18,14 @@ Of course, they are all centered at the same point — that is, the circles are
 
 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.
 
+## Credit
+
+The scoreboard image was created by [habere-et-dispertire][habere-et-dispertire] using [Inkscape][inkscape].
+
 [darts]: https://en.wikipedia.org/wiki/Darts
 [darts-target]: https://en.wikipedia.org/wiki/Darts#/media/File:Darts_in_a_dartboard.jpg
 [concentric]: https://mathworld.wolfram.com/ConcentricCircles.html
 [cartesian-coordinates]: https://www.mathsisfun.com/data/cartesian-coordinates.html
 [real-numbers]: https://www.mathsisfun.com/numbers/real-numbers.html
+[habere-et-dispertire]: https://exercism.org/profiles/habere-et-dispertire
+[inkscape]: https://en.wikipedia.org/wiki/Inkscape

exercises/practice/error-handling/.docs/instructions.md

@@ -5,4 +5,4 @@ Implement various kinds of error handling and resource management.
 An important point of programming is how to handle errors and close resources even if errors occur.
 
 This exercise requires you to handle various errors.
-Because error handling is rather programming language specific you'll have to refer to the tests for your track to see what's exactly required.
+Because error handling is rather programming language specific you'll have to refer to the tests for your track to see what's exactly required.

exercises/practice/isogram/.docs/instructions.md

@@ -11,4 +11,4 @@ Examples of isograms:
 - downstream
 - six-year-old
 
-The word *isograms*, however, is not an isogram, because the s repeats.
+The word _isograms_, however, is not an isogram, because the s repeats.

exercises/practice/leap/.docs/instructions.md

@@ -1,22 +1,3 @@
 # Instructions
 
-Given a year, report if it is a leap year.
-
-The tricky thing here is that a leap year in the Gregorian calendar occurs:
-
-```text
-on every year that is evenly divisible by 4
-  except every year that is evenly divisible by 100
-    unless the year is also evenly divisible by 400
-```
-
-For example, 1997 is not a leap year, but 1996 is.
-1900 is not a leap year, but 2000 is.
-
-## Notes
-
-Though our exercise adopts some very simple rules, there is more to learn!
-
-For a delightful, four minute explanation of the whole leap year phenomenon, go watch [this youtube video][video].
-
-[video]: https://www.youtube.com/watch?v=xX96xng7sAE
+Your task is to determine whether a given year is a leap year.

exercises/practice/leap/.docs/introduction.md

@@ -0,0 +1,16 @@
+# Introduction
+
+A leap year (in the Gregorian calendar) occurs:
+
+- In every year that is evenly divisible by 4
+- Unless the year is evenly divisible by 100, in which case it's only a leap year if the year is also evenly divisible by 400.
+
+Some examples:
+
+- 1997 was not a leap year as it's not divisible by 4.
+- 1900 was not a leap year as it's not divisible by 400
+- 2000 was a leap year!
+
+~~~~exercism/note
+For a delightful, four minute explanation of the whole phenomenon of leap years, check out [this youtube video](https://www.youtube.com/watch?v=xX96xng7sAE).
+~~~~

exercises/practice/list-ops/.docs/instructions.md

@@ -7,13 +7,13 @@ Implement a series of basic list operations, without using existing functions.
 
 The precise number and names of the operations to be implemented will be track dependent to avoid conflicts with existing names, but the general operations you will implement include:
 
-- `append` (*given two lists, add all items in the second list to the end of the first list*);
-- `concatenate` (*given a series of lists, combine all items in all lists into one flattened list*);
-- `filter` (*given a predicate and a list, return the list of all items for which `predicate(item)` is True*);
-- `length` (*given a list, return the total number of items within it*);
-- `map` (*given a function and a list, return the list of the results of applying `function(item)` on all items*);
-- `foldl` (*given a function, a list, and initial accumulator, fold (reduce) each item into the accumulator from the left*);
-- `foldr` (*given a function, a list, and an initial accumulator, fold (reduce) each item into the accumulator from the right*);
-- `reverse` (*given a list, return a list with all the original items, but in reversed order*).
+- `append` (_given two lists, add all items in the second list to the end of the first list_);
+- `concatenate` (_given a series of lists, combine all items in all lists into one flattened list_);
+- `filter` (_given a predicate and a list, return the list of all items for which `predicate(item)` is True_);
+- `length` (_given a list, return the total number of items within it_);
+- `map` (_given a function and a list, return the list of the results of applying `function(item)` on all items_);
+- `foldl` (_given a function, a list, and initial accumulator, fold (reduce) each item into the accumulator from the left_);
+- `foldr` (_given a function, a list, and an initial accumulator, fold (reduce) each item into the accumulator from the right_);
+- `reverse` (_given a list, return a list with all the original items, but in reversed order_).
 
 Note, the ordering in which arguments are passed to the fold functions (`foldl`, `foldr`) is significant.

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

@@ -1,24 +1,39 @@
 # Instructions
 
-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.
-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**.
+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](#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
+
+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/phone-number/.docs/instructions.md

@@ -5,18 +5,20 @@ Clean up user-entered phone numbers so that they can be sent SMS messages.
 The **North American Numbering Plan (NANP)** is a telephone numbering system used by many countries in North America like the United States, Canada or Bermuda.
 All NANP-countries share the same international country code: `1`.
 
-NANP numbers are ten-digit numbers consisting of a three-digit Numbering Plan Area code, commonly known as *area code*, followed by a seven-digit local number.
-The first three digits of the local number represent the *exchange code*, followed by the unique four-digit number which is the *subscriber number*.
+NANP numbers are ten-digit numbers consisting of a three-digit Numbering Plan Area code, commonly known as _area code_, followed by a seven-digit local number.
+The first three digits of the local number represent the _exchange code_, followed by the unique four-digit number which is the _subscriber number_.
 
 The format is usually represented as
 
 ```text
-(NXX)-NXX-XXXX
+NXX NXX-XXXX
 ```
 
 where `N` is any digit from 2 through 9 and `X` is any digit from 0 through 9.
 
-Your task is to clean up differently formatted telephone numbers by removing punctuation and the country code (1) if present.
+Sometimes they also have the country code (represented as `1` or `+1`) prefixed.
+
+Your task is to clean up differently formatted telephone numbers by removing punctuation and the country code if present.
 
 For example, the inputs
 

exercises/practice/protein-translation/.docs/instructions.md

@@ -29,16 +29,16 @@ Note the stop codon `"UAA"` terminates the translation and the final methionine
 
 Below are the codons and resulting Amino Acids needed for the exercise.
 
-Codon                 | Protein
-:---                  | :---
-AUG                   | Methionine
-UUU, UUC              | Phenylalanine
-UUA, UUG              | Leucine
-UCU, UCC, UCA, UCG    | Serine
-UAU, UAC              | Tyrosine
-UGU, UGC              | Cysteine
-UGG                   | Tryptophan
-UAA, UAG, UGA         | STOP
+| Codon              | Protein       |
+| :----------------- | :------------ |
+| AUG                | Methionine    |
+| UUU, UUC           | Phenylalanine |
+| UUA, UUG           | Leucine       |
+| UCU, UCC, UCA, UCG | Serine        |
+| UAU, UAC           | Tyrosine      |
+| UGU, UGC           | Cysteine      |
+| UGG                | Tryptophan    |
+| UAA, UAG, UGA      | STOP          |
 
 Learn more about [protein translation on Wikipedia][protein-translation].