Sync metadata

exercises/practice/atbash-cipher/.meta/config.json

@@ -13,7 +13,7 @@
       ".meta/example.awk"
     ]
   },
-  "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"
 }

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."

exercises/practice/collatz-conjecture/.docs/introduction.md

@@ -0,0 +1,28 @@
+# Introduction
+
+One evening, you stumbled upon an old notebook filled with cryptic scribbles, as though someone had been obsessively chasing an idea.
+On one page, a single question stood out: **Can every number find its way to 1?**
+It was tied to something called the **Collatz Conjecture**, a puzzle that has baffled thinkers for decades.
+
+The rules were deceptively simple.
+Pick any positive integer.
+
+- If it's even, divide it by 2.
+- If it's odd, multiply it by 3 and add 1.
+
+Then, repeat these steps with the result, continuing indefinitely.
+
+Curious, you picked number 12 to test and began the journey:
+
+12 ➜ 6 ➜ 3 ➜ 10 ➜ 5 ➜ 16 ➜ 8 ➜ 4 ➜ 2 ➜ 1
+
+Counting from the second number (6), it took 9 steps to reach 1, and each time the rules repeated, the number kept changing.
+At first, the sequence seemed unpredictable — jumping up, down, and all over.
+Yet, the conjecture claims that no matter the starting number, we'll always end at 1.
+
+It was fascinating, but also puzzling.
+Why does this always seem to work?
+Could there be a number where the process breaks down, looping forever or escaping into infinity?
+The notebook suggested solving this could reveal something profound — and with it, fame, [fortune][collatz-prize], and a place in history awaits whoever could unlock its secrets.
+
+[collatz-prize]: https://mathprize.net/posts/collatz-conjecture/

exercises/practice/collatz-conjecture/.meta/config.json

@@ -14,6 +14,6 @@
     ]
   },
   "blurb": "Calculate the number of steps to reach 1 using the Collatz conjecture.",
-  "source": "An unsolved problem in mathematics named after mathematician Lothar Collatz",
-  "source_url": "https://en.wikipedia.org/wiki/3x_%2B_1_problem"
+  "source": "Wikipedia",
+  "source_url": "https://en.wikipedia.org/wiki/Collatz_conjecture"
 }

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 :)

exercises/practice/hamming/.meta/config.json

@@ -13,7 +13,7 @@
       ".meta/example.awk"
     ]
   },
-  "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/"
 }

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?