feat(curriculum): add permutation generator lab (#56482)

client/i18n/locales/english/intro.json

@@ -3102,7 +3102,12 @@
         ]
       },
       "ndl3": { "title": "242", "intro": [] },
-      "ndl4": { "title": "243", "intro": [] },
+      "lab-permutation-generator": {
+        "title": "Build a Permutation Generator",
+        "intro": [
+          "For this lab, you will build a permutation generator that produces all possible permutations of a given string."
+        ]
+      },
       "review-recursion": {
         "title": "Recursion Review",
         "intro": [

client/src/pages/learn/front-end-development/lab-permutation-generator/index.md

@@ -0,0 +1,9 @@
+---
+title: Introduction to the Build a Permutation Generator
+block: lab-permutation-generator
+superBlock: full-stack-developer
+---
+
+## Introduction to the Build a Permutation Generator
+
+For this lab, you will build a permutation generator that produces all possible permutations of a given string.

curriculum/challenges/_meta/lab-permutation-generator/meta.json

@@ -0,0 +1,11 @@
+{
+  "name": "Build a Permutation Generator",
+  "isUpcomingChange": true,
+  "usesMultifileEditor": true,
+  "dashedName": "lab-permutation-generator",
+  "superBlock": "full-stack-developer",
+  "challengeOrder": [{ "id": "66fe4f33a2cc9b33f4d5cd9b", "title": "Build a Permutation Generator" }],
+  "helpCategory": "JavaScript",
+  "blockType": "lab",
+  "blockLayout": "link"
+}

curriculum/challenges/english/25-front-end-development/lab-permutation-generator/66fe4f33a2cc9b33f4d5cd9b.md

@@ -0,0 +1,166 @@
+---
+id: 66fe4f33a2cc9b33f4d5cd9b
+title: Build a Permutation Generator
+challengeType: 14
+dashedName: build-a-permutation-generator
+---
+
+# --description--
+
+In this lab, you will build a permutation generator that will take a string and return all possible permutations of the characters in the string. For example, the possible permutations of the string `'cat'` are `'cat'`, `'cta'`, `'act'`, `'atc'`, `'tac'`, and `'tca'`.
+
+**Objective:** Fulfill the user stories below and get all the tests to pass to complete the lab. 
+
+**User Stories:**
+
+1. You should create a function named `permuteString`.
+2. The `permuteString` function should take three parameters- a string, a prefix value and an empty array for storing and returning the results. The prefix value would accumulate characters to form a permutation.
+3. Inside the function, you should check if the length of the passed string is `0`. If it is, push the current prefix to the results and return the results.
+4. Iterate over each character in the input string and for each iteration, remove the current character from the string and call the `permuteString` function recursively with updated arguments to build the remaining permutations.
+5. You should return the final results array.
+6. You should ensure that the permutations are unique by removing duplicates.
+
+# --hints--
+
+You should have a function `permuteString`.
+
+```js
+assert.isFunction(permuteString);
+```
+
+You should use recursion in your `permuteString` function.
+
+```js
+assert.match(permuteString.toString(), /permuteString\s*\(/);
+```
+
+`permuteString('far')` should return `[ 'far', 'fra', 'afr', 'arf', 'rfa', 'raf' ]`.
+
+```js
+assert.sameMembers(permuteString('far'), [ 'far', 'fra', 'afr', 'arf', 'rfa', 'raf' ]);
+```
+
+`permuteString('fcc')` should return `[ 'fcc', 'cfc', 'ccf' ]`.
+
+```js
+assert.sameMembers(permuteString('fcc'), [ 'fcc', 'cfc', 'ccf' ]);
+```
+
+`permuteString('p')` should return `[ 'p' ]`.
+
+```js
+assert.deepStrictEqual(permuteString('p'), ['p']);
+```
+
+`permuteString('')` should return `['']`.
+
+```js
+let emptyArr= permuteString('');
+
+// 1 because the empty string is being pushed and is a permutation of itself
+assert.lengthOf(emptyArr, 1); 
+
+```
+
+`permuteString('101')` should return `[ '101', '011', '110' ]`.
+
+```js
+assert.sameMembers(permuteString('101'), [ '101', '011', '110']);
+```
+
+`permuteString` should return the correct results.
+
+```js
+// tests to prevent hard coding
+assert.sameMembers(permuteString('road'), [ 'road',
+  'roda',
+  'raod',
+  'rado',
+  'rdoa',
+  'rdao',
+  'orad',
+  'orda',
+  'oard',
+  'oadr',
+  'odra',
+  'odar',
+  'arod',
+  'ardo',
+  'aord',
+  'aodr',
+  'adro',
+  'ador',
+  'droa',
+  'drao',
+  'dora',
+  'doar',
+  'daro',
+  'daor' ]);
+
+assert.sameMembers(permuteString('fog'), [ 'fog', 
+  'fgo', 
+  'ofg', 
+  'ogf', 
+  'gfo', 
+  'gof' ]);
+
+assert.sameMembers(permuteString('bird'), [ 'bird',
+  'bidr',
+  'brid',
+  'brdi',
+  'bdir',
+  'bdri',
+  'ibrd',
+  'ibdr',
+  'irbd',
+  'irdb',
+  'idbr',
+  'idrb',
+  'rbid',
+  'rbdi',
+  'ribd',
+  'ridb',
+  'rdbi',
+  'rdib',
+  'dbir',
+  'dbri',
+  'dibr',
+  'dirb',
+  'drbi',
+  'drib' ]);
+
+```
+
+# --seed--
+
+## --seed-contents--
+
+```js
+
+```
+
+# --solutions--
+
+```js
+const permuteString = (str, prefix = '', result = []) => {
+  if (str.length === 0) {
+    result.push(prefix);
+    return result;
+  }
+
+  // Sort the string initially to group duplicates
+  const sortedStr = str.split('').sort().join('');
+
+  for (let i = 0; i < sortedStr.length; i++) {
+    if (i > 0 && sortedStr[i] === sortedStr[i - 1]) {
+      // Skip duplicate characters
+      continue;
+    }
+
+    const rem = sortedStr.slice(0, i) + sortedStr.slice(i + 1);
+    permuteString(rem, prefix + sortedStr[i], result);
+  }
+
+  return result;
+};
+```

curriculum/superblock-structure/full-stack.json

@@ -497,6 +497,7 @@
               "dashedName": "lecture-understanding-recursion-and-the-call-stack"
             },
             { "dashedName": "workshop-decimal-to-binary-converter" },
+            { "dashedName": "lab-permutation-generator" },
             { "dashedName": "review-recursion" },
             { "dashedName": "quiz-recursion" }
           ]