Sync metadata, docs and tests (#706)

* update docs and metadata

* remove reimplemented test and add new one

exercises/practice/hamming/.docs/instructions.md

@@ -1,6 +1,6 @@
 # Instructions
 
-Calculate the Hamming Distance between two DNA strands.
+Calculate the Hamming distance between two DNA strands.
 
 Your body is made up of cells that contain DNA.
 Those cells regularly wear out and need replacing, which they achieve by dividing into daughter cells.
@@ -9,18 +9,18 @@ In fact, the average human body experiences about 10 quadrillion cell divisions
 When cells divide, their DNA replicates too.
 Sometimes during this process mistakes happen and single pieces of DNA get encoded with the incorrect information.
 If we compare two strands of DNA and count the differences between them we can see how many mistakes occurred.
-This is known as the "Hamming Distance".
+This is known as the "Hamming distance".
 
-We read DNA using the letters C,A,G and T.
+We read DNA using the letters C, A, G and T.
 Two strands might look like this:
 
     GAGCCTACTAACGGGAT
     CATCGTAATGACGGCCT
     ^ ^ ^  ^ ^    ^^
 
-They have 7 differences, and therefore the Hamming Distance is 7.
+They have 7 differences, and therefore the Hamming distance is 7.
 
-The Hamming Distance is useful for lots of things in science, not just biology, so it's a nice phrase to be familiar with :)
+The Hamming distance is useful for lots of things in science, not just biology, so it's a nice phrase to be familiar with :)
 
 ## Implementation notes
 

exercises/practice/luhn/.docs/instructions.md

@@ -22,7 +22,8 @@ The first step of the Luhn algorithm is to double every second digit, starting f
 We will be doubling
 
 ```text
-4_3_ 3_9_ 0_4_ 6_6_
+4539 3195 0343 6467
+↑ ↑  ↑ ↑  ↑ ↑  ↑ ↑  (double these)
 ```
 
 If doubling the number results in a number greater than 9 then subtract 9 from the product.

exercises/practice/pascals-triangle/.docs/instructions.md

@@ -1,14 +1,35 @@
 # Instructions
 
-Compute Pascal's triangle up to a given number of rows.
+Your task is to output the first N rows of Pascal's triangle.
 
-In Pascal's Triangle each number is computed by adding the numbers to the right and left of the current position in the previous row.
+[Pascal's triangle][wikipedia] is a triangular array of positive integers.
+
+In Pascal's triangle, the number of values in a row is equal to its row number (which starts at one).
+Therefore, the first row has one value, the second row has two values, and so on.
+
+The first (topmost) row has a single value: `1`.
+Subsequent rows' values are computed by adding the numbers directly to the right and left of the current position in the previous row.
+
+If the previous row does _not_ have a value to the left or right of the current position (which only happens for the leftmost and rightmost positions), treat that position's value as zero (effectively "ignoring" it in the summation).
+
+## Example
+
+Let's look at the first 5 rows of Pascal's Triangle:
 
 ```text
     1
    1 1
   1 2 1
  1 3 3 1
 1 4 6 4 1
-# ... etc
 ```
+
+The topmost row has one value, which is `1`.
+
+The leftmost and rightmost values have only one preceding position to consider, which is the position to its right respectively to its left.
+With the topmost value being `1`, it follows from this that all the leftmost and rightmost values are also `1`.
+
+The other values all have two positions to consider.
+For example, the fifth row's (`1 4 6 4 1`) middle value is `6`, as the values to its left and right in the preceding row are `3` and `3`:
+
+[wikipedia]: https://en.wikipedia.org/wiki/Pascal%27s_triangle

exercises/practice/pascals-triangle/.docs/introduction.md

@@ -0,0 +1,22 @@
+# Introduction
+
+With the weather being great, you're not looking forward to spending an hour in a classroom.
+Annoyed, you enter the class room, where you notice a strangely satisfying triangle shape on the blackboard.
+Whilst waiting for your math teacher to arrive, you can't help but notice some patterns in the triangle: the outer values are all ones, each subsequent row has one more value than its previous row and the triangle is symmetrical.
+Weird!
+
+Not long after you sit down, your teacher enters the room and explains that this triangle is the famous [Pascal's triangle][wikipedia].
+
+Over the next hour, your teacher reveals some amazing things hidden in this triangle:
+
+- It can be used to compute how many ways you can pick K elements from N values.
+- It contains the Fibonacci sequence.
+- If you color odd and even numbers differently, you get a beautiful pattern called the [Sierpiński triangle][wikipedia-sierpinski-triangle].
+
+The teacher implores you and your classmates to lookup other uses, and assures you that there are lots more!
+At that moment, the school bell rings.
+You realize that for the past hour, you were completely absorbed in learning about Pascal's triangle.
+You quickly grab your laptop from your bag and go outside, ready to enjoy both the sunshine _and_ the wonders of Pascal's triangle.
+
+[wikipedia]: https://en.wikipedia.org/wiki/Pascal%27s_triangle
+[wikipedia-sierpinski-triangle]: https://en.wikipedia.org/wiki/Sierpi%C5%84ski_triangle

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/protein-translation/.meta/tests.toml

@@ -87,11 +87,15 @@ description = "Translation stops if STOP codon in middle of three-codon sequence
 [2c2a2a60-401f-4a80-b977-e0715b23b93d]
 description = "Translation stops if STOP codon in middle of six-codon sequence"
 
+[f6f92714-769f-4187-9524-e353e8a41a80]
+description = "Sequence of two non-STOP codons does not translate to a STOP codon"
+
 [1e75ea2a-f907-4994-ae5c-118632a1cb0f]
 description = "Non-existing codon can't translate"
 
 [9eac93f3-627a-4c90-8653-6d0a0595bc6f]
 description = "Unknown amino acids, not part of a codon, can't translate"
+reimplements = "1e75ea2a-f907-4994-ae5c-118632a1cb0f"
 
 [9d73899f-e68e-4291-b1e2-7bf87c00f024]
 description = "Incomplete RNA sequence can't translate"

exercises/practice/protein-translation/tests/Tests.elm

@@ -137,11 +137,6 @@ tests =
                 \() ->
                     ProteinTranslation.proteins "UGGUGUUAUUAAUGGUUU"
                         |> Expect.equal (Ok [ "Tryptophan", "Cysteine", "Tyrosine" ])
-        , skip <|
-            test "Non-existing codon can't translate" <|
-                \() ->
-                    ProteinTranslation.proteins "AAA"
-                        |> Expect.equal (Err InvalidCodon)
         , skip <|
             test "Unknown amino acids, not part of a codon, can't translate" <|
                 \() ->
@@ -157,4 +152,9 @@ tests =
                 \() ->
                     ProteinTranslation.proteins "UUCUUCUAAUGGU"
                         |> Expect.equal (Ok [ "Phenylalanine", "Phenylalanine" ])
+        , skip <|
+            test "Sequence of two non-STOP codons does not translate to a STOP codon" <|
+                \() ->
+                    ProteinTranslation.proteins "AUGAUG"
+                        |> Expect.equal (Ok [ "Methionine", "Methionine" ])
         ]

exercises/practice/yacht/.meta/config.json

@@ -14,6 +14,6 @@
     ]
   },
   "blurb": "Score a single throw of dice in the game Yacht.",
-  "source": "James Kilfiger, using wikipedia",
+  "source": "James Kilfiger, using Wikipedia",
   "source_url": "https://en.wikipedia.org/wiki/Yacht_(dice_game)"
 }

exercises/practice/zebra-puzzle/.docs/instructions.md

@@ -12,20 +12,20 @@ The following 15 statements are all known to be true:
 1. There are five houses.
 2. The Englishman lives in the red house.
 3. The Spaniard owns the dog.
-4. Coffee is drunk in the green house.
+4. The person in the green house drinks coffee.
 5. The Ukrainian drinks tea.
 6. The green house is immediately to the right of the ivory house.
-7. The Old Gold smoker owns snails.
-8. Kools are smoked in the yellow house.
-9. Milk is drunk in the middle house.
+7. The snail owner likes to go dancing.
+8. The person in the yellow house is a painter.
+9. The person in the middle house drinks milk.
 10. The Norwegian lives in the first house.
-11. The man who smokes Chesterfields lives in the house next to the man with the fox.
-12. Kools are smoked in the house next to the house where the horse is kept.
-13. The Lucky Strike smoker drinks orange juice.
-14. The Japanese smokes Parliaments.
+11. The person who enjoys reading lives in the house next to the person with the fox.
+12. The painter's house is next to the house with the horse.
+13. The person who plays football drinks orange juice.
+14. The Japanese person plays chess.
 15. The Norwegian lives next to the blue house.
 
-Additionally, each of the five houses is painted a different color, and their inhabitants are of different national extractions, own different pets, drink different beverages and smoke different brands of cigarettes.
+Additionally, each of the five houses is painted a different color, and their inhabitants are of different national extractions, own different pets, drink different beverages and engage in different hobbies.
 
 ~~~~exercism/note
 There are 24 billion (5!⁵ = 24,883,200,000) possible solutions, so try ruling out as many solutions as possible.

exercises/practice/zebra-puzzle/.docs/introduction.md

@@ -1,7 +1,7 @@
 # Introduction
 
 The Zebra Puzzle is a famous logic puzzle in which there are five houses, each painted a different color.
-The houses have different inhabitants, who have different nationalities, own different pets, drink different beverages and smoke different brands of cigarettes.
+The houses have different inhabitants, who have different nationalities, own different pets, drink different beverages and enjoy different hobbies.
 
 To help you solve the puzzle, you're given 15 statements describing the solution.
 However, only by combining the information in _all_ statements will you be able to find the solution to the puzzle.