Sync problem specs (#538)

BNAndras · web-flow · commit 6bc703b1eb41 · 2025-04-14T18:41:43.000-04:00
* Sync docs

* Sync metadata

* Sync filepaths
diff --git a/exercises/practice/anagram/.docs/instructions.md b/exercises/practice/anagram/.docs/instructions.md
@@ -1,13 +1,12 @@
 # Instructions
 
-Your task is to, given a target word and a set of candidate words, to find the subset of the candidates that are anagrams of the target.
+Given a target word and one or more candidate words, your task is to find the candidates that are anagrams of the target.
 
 An anagram is a rearrangement of letters to form a new word: for example `"owns"` is an anagram of `"snow"`.
 A word is _not_ its own anagram: for example, `"stop"` is not an anagram of `"stop"`.
 
-The target and candidates are words of one or more ASCII alphabetic characters (`A`-`Z` and `a`-`z`).
-Lowercase and uppercase characters are equivalent: for example, `"PoTS"` is an anagram of `"sTOp"`, but `StoP` is not an anagram of `sTOp`.
-The anagram set is the subset of the candidate set that are anagrams of the target (in any order).
-Words in the anagram set should have the same letter case as in the candidate set.
+The target word and candidate words are made up of one or more ASCII alphabetic characters (`A`-`Z` and `a`-`z`).
+Lowercase and uppercase characters are equivalent: for example, `"PoTS"` is an anagram of `"sTOp"`, but `"StoP"` is not an anagram of `"sTOp"`.
+The words you need to find should be taken from the candidate words, using the same letter case.
 
-Given the target `"stone"` and candidates `"stone"`, `"tones"`, `"banana"`, `"tons"`, `"notes"`, `"Seton"`, the anagram set is `"tones"`, `"notes"`, `"Seton"`.
+Given the target `"stone"` and the candidate words `"stone"`, `"tones"`, `"banana"`, `"tons"`, `"notes"`, and `"Seton"`, the anagram words you need to find are `"tones"`, `"notes"`, and `"Seton"`.
diff --git a/exercises/practice/atbash-cipher/.docs/instructions.md b/exercises/practice/atbash-cipher/.docs/instructions.md
@@ -1,6 +1,6 @@
 # Instructions
 
-Create an implementation of the atbash cipher, an ancient encryption system created in the Middle East.
+Create an implementation of the Atbash cipher, an ancient encryption system created in the Middle East.
 
 The Atbash cipher is a simple substitution cipher that relies on transposing all the letters in the alphabet such that the resulting alphabet is backwards.
 The first letter is replaced with the last letter, the second with the second-last, and so on.
diff --git a/exercises/practice/atbash-cipher/.meta/config.json b/exercises/practice/atbash-cipher/.meta/config.json
@@ -26,7 +26,7 @@
       "atbash_cipher.mli"
     ]
   },
-  "blurb": "Create an implementation of the atbash cipher, an ancient encryption system created in the Middle East.",
+  "blurb": "Create an implementation of the Atbash cipher, an ancient encryption system created in the Middle East.",
   "source": "Wikipedia",
   "source_url": "https://en.wikipedia.org/wiki/Atbash"
 }
diff --git a/exercises/practice/change/.docs/instructions.md b/exercises/practice/change/.docs/instructions.md
@@ -1,14 +1,8 @@
 # Instructions
 
-Correctly determine the fewest number of coins to be given to a customer such that the sum of the coins' value would equal the correct amount of change.
+Determine the fewest number of coins to give a customer so that the sum of their values equals the correct amount of change.
 
-## For example
+## Examples
 
-- An input of 15 with [1, 5, 10, 25, 100] should return one nickel (5) and one dime (10) or [5, 10]
-- An input of 40 with [1, 5, 10, 25, 100] should return one nickel (5) and one dime (10) and one quarter (25) or [5, 10, 25]
-
-## Edge cases
-
-- Does your algorithm work for any given set of coins?
-- Can you ask for negative change?
-- Can you ask for a change value smaller than the smallest coin value?
+- An amount of 15 with available coin values [1, 5, 10, 25, 100] should return one coin of value 5 and one coin of value 10, or [5, 10].
+- An amount of 40 with available coin values [1, 5, 10, 25, 100] should return one coin of value 5, one coin of value 10, and one coin of value 25, or [5, 10, 25].
diff --git a/exercises/practice/change/.docs/introduction.md b/exercises/practice/change/.docs/introduction.md
@@ -0,0 +1,26 @@
+# Introduction
+
+In the mystical village of Coinholt, you stand behind the counter of your bakery, arranging a fresh batch of pastries.
+The door creaks open, and in walks Denara, a skilled merchant with a keen eye for quality goods.
+After a quick meal, she slides a shimmering coin across the counter, representing a value of 100 units.
+
+You smile, taking the coin, and glance at the total cost of the meal: 88 units.
+That means you need to return 12 units in change.
+
+Denara holds out her hand expectantly.
+"Just give me the fewest coins," she says with a smile.
+"My pouch is already full, and I don't want to risk losing them on the road."
+
+You know you have a few options.
+"We have Lumis (worth 10 units), Viras (worth 5 units), and Zenth (worth 2 units) available for change."
+
+You quickly calculate the possibilities in your head:
+
+- one Lumis (1 × 10 units) + one Zenth (1 × 2 units) = 2 coins total
+- two Viras (2 × 5 units) + one Zenth (1 × 2 units) = 3 coins total
+- six Zenth (6 × 2 units) = 6 coins total
+
+"The best choice is two coins: one Lumis and one Zenth," you say, handing her the change.
+
+Denara smiles, clearly impressed.
+"As always, you've got it right."
diff --git a/exercises/practice/dominoes/.docs/instructions.md b/exercises/practice/dominoes/.docs/instructions.md
@@ -2,7 +2,9 @@
 
 Make a chain of dominoes.
 
-Compute a way to order a given set of dominoes in such a way that they form a correct domino chain (the dots on one half of a stone match the dots on the neighboring half of an adjacent stone) and that dots on the halves of the stones which don't have a neighbor (the first and last stone) match each other.
+Compute a way to order a given set of domino stones so that they form a correct domino chain.
+In the chain, the dots on one half of a stone must match the dots on the neighboring half of an adjacent stone.
+Additionally, the dots on the halves of the stones without neighbors (the first and last stone) must match each other.
 
 For example given the stones `[2|1]`, `[2|3]` and `[1|3]` you should compute something
 like `[1|2] [2|3] [3|1]` or `[3|2] [2|1] [1|3]` or `[1|3] [3|2] [2|1]` etc, where the first and last numbers are the same.
diff --git a/exercises/practice/dominoes/.docs/introduction.md b/exercises/practice/dominoes/.docs/introduction.md
@@ -0,0 +1,13 @@
+# Introduction
+
+In Toyland, the trains are always busy delivering treasures across the city, from shiny marbles to rare building blocks.
+The tracks they run on are made of colorful domino-shaped pieces, each marked with two numbers.
+For the trains to move, the dominoes must form a perfect chain where the numbers match.
+
+Today, an urgent delivery of rare toys is on hold.
+You've been handed a set of track pieces to inspect.
+If they can form a continuous chain, the train will be on its way, bringing smiles across Toyland.
+If not, the set will be discarded, and another will be tried.
+
+The toys are counting on you to solve this puzzle.
+Will the dominoes connect the tracks and send the train rolling, or will the set be left behind?
diff --git a/exercises/practice/eliuds-eggs/.docs/introduction.md b/exercises/practice/eliuds-eggs/.docs/introduction.md
@@ -58,7 +58,7 @@ The position information encoding is calculated as follows:
 
 ### Decimal number on the display
 
-16
+8
 
 ### Actual eggs in the coop
 
diff --git a/exercises/practice/grade-school/.docs/instructions.md b/exercises/practice/grade-school/.docs/instructions.md
@@ -1,21 +1,21 @@
 # Instructions
 
-Given students' names along with the grade that they are in, create a roster for the school.
+Given students' names along with the grade they are in, create a roster for the school.
 
 In the end, you should be able to:
 
-- Add a student's name to the roster for a grade
+- Add a student's name to the roster for a grade:
   - "Add Jim to grade 2."
   - "OK."
-- Get a list of all students enrolled in a grade
+- Get a list of all students enrolled in a grade:
   - "Which students are in grade 2?"
-  - "We've only got Jim just now."
+  - "We've only got Jim right now."
 - Get a sorted list of all students in all grades.
-  Grades should sort as 1, 2, 3, etc., and students within a grade should be sorted alphabetically by name.
-  - "Who all is enrolled in school right now?"
+  Grades should be sorted as 1, 2, 3, etc., and students within a grade should be sorted alphabetically by name.
+  - "Who is enrolled in school right now?"
   - "Let me think.
-    We have Anna, Barb, and Charlie in grade 1, Alex, Peter, and Zoe in grade 2 and Jim in grade 5.
-    So the answer is: Anna, Barb, Charlie, Alex, Peter, Zoe and Jim"
+    We have Anna, Barb, and Charlie in grade 1, Alex, Peter, and Zoe in grade 2, and Jim in grade 5.
+    So the answer is: Anna, Barb, Charlie, Alex, Peter, Zoe, and Jim."
 
-Note that all our students only have one name (It's a small town, what do you want?) and each student cannot be added more than once to a grade or the roster.
-In fact, when a test attempts to add the same student more than once, your implementation should indicate that this is incorrect.
+Note that all our students only have one name (it's a small town, what do you want?), and each student cannot be added more than once to a grade or the roster.
+If a test attempts to add the same student more than once, your implementation should indicate that this is incorrect.
diff --git a/exercises/practice/hamming/.docs/instructions.md b/exercises/practice/hamming/.docs/instructions.md
@@ -1,26 +1,15 @@
 # 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.
-In fact, the average human body experiences about 10 quadrillion cell divisions in a lifetime!
-
-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".
-
-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.
-
-The Hamming Distance is useful for lots of things in science, not just biology, so it's a nice phrase to be familiar with :)
+They have 7 differences, and therefore the Hamming distance is 7.
 
 ## Implementation notes
 
diff --git a/exercises/practice/hamming/.docs/introduction.md b/exercises/practice/hamming/.docs/introduction.md
@@ -0,0 +1,12 @@
+# Introduction
+
+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.
+In fact, the average human body experiences about 10 quadrillion cell divisions in a lifetime!
+
+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".
+
+The Hamming distance is useful in many areas of science, not just biology, so it's a nice phrase to be familiar with :)
diff --git a/exercises/practice/hamming/.meta/config.json b/exercises/practice/hamming/.meta/config.json
@@ -26,7 +26,7 @@
       "hamming.mli"
     ]
   },
-  "blurb": "Calculate the Hamming difference between two DNA strands.",
+  "blurb": "Calculate the Hamming distance between two DNA strands.",
   "source": "The Calculating Point Mutations problem at Rosalind",
   "source_url": "https://rosalind.info/problems/hamm/"
 }
diff --git a/exercises/practice/knapsack/.docs/instructions.md b/exercises/practice/knapsack/.docs/instructions.md
@@ -1,11 +1,11 @@
 # Instructions
 
-Your task is to determine which items to take so that the total value of his selection is maximized, taking into account the knapsack's carrying capacity.
+Your task is to determine which items to take so that the total value of her selection is maximized, taking into account the knapsack's carrying capacity.
 
 Items will be represented as a list of items.
 Each item will have a weight and value.
 All values given will be strictly positive.
-Bob can take only one of each item.
+Lhakpa can take only one of each item.
 
 For example:
 
@@ -21,5 +21,5 @@ Knapsack Maximum Weight: 10
 ```
 
 For the above, the first item has weight 5 and value 10, the second item has weight 4 and value 40, and so on.
-In this example, Bob should take the second and fourth item to maximize his value, which, in this case, is 90.
-He cannot get more than 90 as his knapsack has a weight limit of 10.
+In this example, Lhakpa should take the second and fourth item to maximize her value, which, in this case, is 90.
+She cannot get more than 90 as her knapsack has a weight limit of 10.
diff --git a/exercises/practice/knapsack/.docs/introduction.md b/exercises/practice/knapsack/.docs/introduction.md
@@ -1,8 +1,10 @@
 # Introduction
 
-Bob is a thief.
-After months of careful planning, he finally manages to crack the security systems of a fancy store.
+Lhakpa is a [Sherpa][sherpa] mountain guide and porter.
+After months of careful planning, the expedition Lhakpa works for is about to leave.
+She will be paid the value she carried to the base camp.
 
-In front of him are many items, each with a value and weight.
-Bob would gladly take all of the items, but his knapsack can only hold so much weight.
-Bob has to carefully consider which items to take so that the total value of his selection is maximized.
+In front of her are many items, each with a value and weight.
+Lhakpa would gladly take all of the items, but her knapsack can only hold so much weight.
+
+[sherpa]: https://en.wikipedia.org/wiki/Sherpa_people#Mountaineering
diff --git a/exercises/practice/knapsack/.meta/config.json b/exercises/practice/knapsack/.meta/config.json
@@ -11,6 +11,9 @@
     ],
     "example": [
       ".meta/example.ml"
+    ],
+    "editor": [
+      "knapsack.mli"
     ]
   },
   "blurb": "Given a knapsack that can only carry a certain weight, determine which items to put in the knapsack in order to maximize their combined value.",
diff --git a/exercises/practice/leap/.meta/config.json b/exercises/practice/leap/.meta/config.json
@@ -31,5 +31,5 @@
   },
   "blurb": "Determine whether a given year is a leap year.",
   "source": "CodeRanch Cattle Drive, Assignment 3",
-  "source_url": "https://coderanch.com/t/718816/Leap"
+  "source_url": "https://web.archive.org/web/20240907033714/https://coderanch.com/t/718816/Leap"
 }
diff --git a/exercises/practice/luhn/.docs/instructions.md b/exercises/practice/luhn/.docs/instructions.md
@@ -1,64 +1,68 @@
 # Instructions
 
-Given a number determine whether or not it is valid per the Luhn formula.
+Determine whether a number is valid according to the [Luhn formula][luhn].
 
-The [Luhn algorithm][luhn] is a simple checksum formula used to validate a variety of identification numbers, such as credit card numbers and Canadian Social Insurance Numbers.
+The number will be provided as a string.
 
-The task is to check if a given string is valid.
-
-## Validating a Number
+## Validating a number
 
 Strings of length 1 or less are not valid.
 Spaces are allowed in the input, but they should be stripped before checking.
 All other non-digit characters are disallowed.
 
-### Example 1: valid credit card number
+## Examples
 
-```text
-4539 3195 0343 6467
-```
+### Valid credit card number
 
-The first step of the Luhn algorithm is to double every second digit, starting from the right.
-We will be doubling
+The number to be checked is `4539 3195 0343 6467`.
+
+The first step of the Luhn algorithm is to start at the end of the number and double every second digit, beginning with the second digit from the right and moving left.
 
 ```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.
-The results of our doubling:
+If the result of doubling a digit is greater than 9, we subtract 9 from that result.
+We end up with:
 
 ```text
 8569 6195 0383 3437
 ```
 
-Then sum all of the digits:
+Finally, we sum all digits.
+If the sum is evenly divisible by 10, the original number is valid.
 
 ```text
-8+5+6+9+6+1+9+5+0+3+8+3+3+4+3+7 = 80
+8 + 5 + 6 + 9 + 6 + 1 + 9 + 5 + 0 + 3 + 8 + 3 + 3 + 4 + 3 + 7 = 80
 ```
 
-If the sum is evenly divisible by 10, then the number is valid.
-This number is valid!
+80 is evenly divisible by 10, so number `4539 3195 0343 6467` is valid!
+
+### Invalid Canadian SIN
+
+The number to be checked is `066 123 468`.
 
-### Example 2: invalid credit card number
+We start at the end of the number and double every second digit, beginning with the second digit from the right and moving left.
 
 ```text
-8273 1232 7352 0569
+066 123 478
+ ↑  ↑ ↑  ↑  (double these)
 ```
 
-Double the second digits, starting from the right
+If the result of doubling a digit is greater than 9, we subtract 9 from that result.
+We end up with:
 
 ```text
-7253 2262 5312 0539
+036 226 458
 ```
 
-Sum the digits
+We sum the digits:
 
 ```text
-7+2+5+3+2+2+6+2+5+3+1+2+0+5+3+9 = 57
+0 + 3 + 6 + 2 + 2 + 6 + 4 + 5 + 8 = 36
 ```
 
-57 is not evenly divisible by 10, so this number is not valid.
+36 is not evenly divisible by 10, so number `066 123 478` is not valid!
 
 [luhn]: https://en.wikipedia.org/wiki/Luhn_algorithm
diff --git a/exercises/practice/luhn/.docs/introduction.md b/exercises/practice/luhn/.docs/introduction.md
@@ -0,0 +1,11 @@
+# Introduction
+
+At the Global Verification Authority, you've just been entrusted with a critical assignment.
+Across the city, from online purchases to secure logins, countless operations rely on the accuracy of numerical identifiers like credit card numbers, bank account numbers, transaction codes, and tracking IDs.
+The Luhn algorithm is a simple checksum formula used to help identify mistyped numbers.
+
+A batch of identifiers has just arrived on your desk.
+All of them must pass the Luhn test to ensure they're legitimate.
+If any fail, they'll be flagged as invalid, preventing mistakes such as incorrect transactions or failed account verifications.
+
+Can you ensure this is done right? The integrity of many services depends on you.
diff --git a/exercises/practice/matching-brackets/.docs/instructions.md b/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.
diff --git a/exercises/practice/matching-brackets/.docs/introduction.md b/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™.
diff --git a/exercises/practice/phone-number/.docs/introduction.md b/exercises/practice/phone-number/.docs/introduction.md
@@ -0,0 +1,12 @@
+# Introduction
+
+You've joined LinkLine, a leading communications company working to ensure reliable connections for everyone.
+The team faces a big challenge: users submit phone numbers in all sorts of formats — dashes, spaces, dots, parentheses, and even prefixes.
+Some numbers are valid, while others are impossible to use.
+
+Your mission is to turn this chaos into order.
+You'll clean up valid numbers, formatting them appropriately for use in the system.
+At the same time, you'll identify and filter out any invalid entries.
+
+The success of LinkLine's operations depends on your ability to separate the useful from the unusable.
+Are you ready to take on the challenge and keep the connections running smoothly?
diff --git a/exercises/practice/rna-transcription/.docs/instructions.md b/exercises/practice/rna-transcription/.docs/instructions.md
diff --git a/exercises/practice/rna-transcription/.meta/config.json b/exercises/practice/rna-transcription/.meta/config.json
diff --git a/exercises/practice/say/.docs/instructions.md b/exercises/practice/say/.docs/instructions.md
diff --git a/exercises/practice/say/.meta/config.json b/exercises/practice/say/.meta/config.json
diff --git a/exercises/practice/sieve/.docs/instructions.md b/exercises/practice/sieve/.docs/instructions.md
diff --git a/exercises/practice/sieve/.meta/config.json b/exercises/practice/sieve/.meta/config.json
diff --git a/exercises/practice/space-age/.docs/instructions.md b/exercises/practice/space-age/.docs/instructions.md
diff --git a/exercises/practice/space-age/.docs/introduction.md b/exercises/practice/space-age/.docs/introduction.md

Original file line number	Diff line number	Diff line change
`@@ -26,7 +26,7 @@`
`26`	`26`	`"atbash_cipher.mli"`
`27`	`27`	`]`
`28`	`28`	`},`
`29`		`- "blurb": "Create an implementation of the atbash cipher, an ancient encryption system created in the Middle East.",`
	`29`	`+ "blurb": "Create an implementation of the Atbash cipher, an ancient encryption system created in the Middle East.",`
`30`	`30`	`"source": "Wikipedia",`
`31`	`31`	`"source_url": "https://en.wikipedia.org/wiki/Atbash"`
`32`	`32`	`}`