London | 25-SDC-July | Ali Qassab | Sprint 1 | Analyse and refactor

.github/ISSUE_TEMPLATE/config.yml

@@ -9,3 +9,6 @@ contact_links:
   - name: CYF Slack
     url: codeyourfuture.slack.com
     about: Come to #cyf-curriculum and chat
+  - name: CYF Tech Ed
+    url: https://github.com/orgs/CodeYourFuture/teams/mentors
+    about: CYF mentors on Github

.github/ISSUE_TEMPLATE/pd-assignment.yml

@@ -0,0 +1,59 @@
+name: PD Coursework
+description: Assign a piece of PD coursework
+title: "[PD] <title>"
+labels: [PD, 🏝 Priority Stretch, 🐇 Size Small, 📅 Sprint 1]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to assign this coursework!
+  - type: input
+    attributes:
+      label: Coursework content
+    validations:
+      required: true
+  - type: input
+    attributes:
+      label: Estimated time in hours
+      description: (PD has max 4 per week total)
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: What is the purpose of this assignment?
+      description: Clearly explain the purpose of this assignment and how trainees can evaluate this.
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: How to submit
+      description: State in clear steps how a trainee can submit this assignment.
+      placeholder: |
+        Copy the Google doc to your own Google Drive
+        Complete the work assigned
+        When you are ready, move your document to your class Drive
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Anything else?
+      description: |
+        Links? References? Anything that will give more context
+
+        Tip: You can attach images or log files by clicking this area to highlight it and then dragging files in.
+  - type: markdown
+    attributes:
+      value: |
+        **Thank you so much.**
+
+        Please now complete this ticket by filling in the options on the sidebar.
+
+        1. Update labels
+        - priority -- is this coursework key, mandatory, or stretch?
+        - size -- help trainees plan their time with rough estimation
+        2. Add to project backlog
+        - add to the project named the same as this repo
+        - fill in custom fields -- priority, size, hours, week -- to match this issue
+
+        Once your ticket is complete, you may like to check it out on the example project board attached to this repo.
+        This is so you understand how trainees will use your work.

.github/ISSUE_TEMPLATE/coursework.yml → .github/ISSUE_TEMPLATE/tech-ed-assignment.yml

@@ -1,20 +1,20 @@
-name: Coursework
-description: Assign a piece of coursework
+name: Tech Ed Coursework
+description: Assign a piece of technical coursework
 title: "<title>"
-labels: [Tech Ed, 🏕 Priority Mandatory, 🐂 Size Medium, 📅 Module 1]
+labels: [Tech Ed, 🏕 Priority Mandatory, 🐂 Size Medium, 📅 Sprint 1]
 body:
   - type: markdown
     attributes:
       value: |
-        Thanks for taking the time to assign this coursework! 
+        Thanks for taking the time to assign this coursework!
 
-        To support our trainees with planning and prioritising their own learning journey, we want our coursework assignments to be more informative. 
+        To support our trainees with planning and prioritising their own learning journey, we want our coursework assignments to be more informative.
         We don't just want to tell them what to do, we want to tell them stuff like:
         - why we are doing it
         - what it's "for" (problem-solving, debugging, etc)
         - how long they should spend on it, maximum
-        - how to get help 
-        - how to review it with answers 
+        - how to get help
+        - how to review it with answers
         - how to get it reviewed from mentors and peers
   - type: input
     attributes:
@@ -26,7 +26,7 @@ body:
       label: Learning Objectives
       description: https://common.codeyourfuture.io/common-theme/shortcodes/objectives/
       placeholder: |
-        <!--{{<objectives}}--> 
+        <!--{{<objectives}}-->
         - [ ] CYF format, task list formatting
         <!--{{</objectives}}-->
   - type: textarea
@@ -38,6 +38,7 @@ body:
   - type: input
     attributes:
       label: Maximum time in hours
+      description: (Tech has max 16 per week total)
     validations:
       required: true
   - type: textarea
@@ -79,7 +80,7 @@ body:
         1. Update labels
         - priority -- is this coursework key, mandatory, or stretch? Pick one.
         - size -- help trainees plan their time with rough estimation. Pick one
-        - topics -- add all that seem relevant to you. 
+        - topics -- add all that seem relevant to you.
         2. Add a Sprint label to add to the backlog view
         - sprint 1,2,3,4
 

.github/pull_request_template.md

@@ -2,27 +2,35 @@
 
 You must title your PR like this:
 
-REGION | COHORT_NAME | FIRST_NAME LAST_NAME | PROJ_NAME
+Region | Cohort | FirstName LastName | Sprint | Assignment Title
 
 For example,
 
-London | March-2025 | Carol Owen | Wireframe
+London | 25-ITP-May | Carol Owen | Sprint 1 | Alarm Clock
 
-Complete the task list below this message.
-If your PR is rejected, check the task list.
+Fill in the template below - remove any sections that don't apply.
+
+Complete the self checklist - replace each empty box in the checklist [ ] with a [x].
+
+Add the label "Needs Review" and you will get review.
+
+Respond to volunteer reviews until the volunteer marks it as "Complete".
 
 -->
 
 ## Learners, PR Template
 
 Self checklist
 
-- [ ] I have committed my files one by one, on purpose, and for a reason
-- [ ] I have titled my PR with REGION | COHORT_NAME | FIRST_NAME LAST_NAME | PROJ_NAME
+- [ ] I have titled my PR with Region | Cohort | FirstName LastName | Sprint | Assignment Title
+- [ ] My changes meet the requirements of the task
 - [ ] I have tested my changes
 - [ ] My changes follow the [style guide](https://curriculum.codeyourfuture.io/guides/reviewing/style-guide/)
-- [ ] My changes meet the [requirements](./README.md) of this task
+
+## Changelist
+
+Briefly explain your PR.
 
 ## Questions
 
-Ask any questions you have for your reviewer. Delete this section if there are none.
+Ask any questions you have for your reviewer.

.github/workflows/validate-pr-metadata.yml

@@ -0,0 +1,18 @@
+name: Validate PR Metadata
+on:
+  pull_request_target:
+    types:
+      - labeled
+      - unlabeled
+      - opened
+      - edited
+      - reopened
+
+jobs:
+  validate_pr_metadata:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: CodeYourFuture/actions/validate-pr-metadata@main
+        with:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

Sprint-1/JavaScript/calculateSumAndProduct/calculateSumAndProduct.js

@@ -9,26 +9,53 @@
  *   "product": 30 // 2 * 3 * 5
  * }
  *
- * Time Complexity:
- * Space Complexity:
- * Optimal Time Complexity:
+ * Time Complexity: O(n) - Single pass through the array
+ * Space Complexity: O(1) - Only using constant extra space
+ * Optimal Time Complexity: O(n) - Cannot do better than linear time
  *
  * @param {Array<number>} numbers - Numbers to process
  * @returns {Object} Object containing running total and product
  */
 export function calculateSumAndProduct(numbers) {
-  let sum = 0;
-  for (const num of numbers) {
-    sum += num;
-  }
+  // OPTIMIZED IMPLEMENTATION: Single pass algorithm
+  // Previous implementation used two separate loops (2n operations)
+  // This version combines both calculations in one loop (n operations)
+
+  let sum = 0; // O(1) space
+  let product = 1; // O(1) space
 
-  let product = 1;
+  // Single pass through array: O(n) time complexity
   for (const num of numbers) {
-    product *= num;
+    sum += num; // O(1) operation per element
+    product *= num; // O(1) operation per element
   }
 
-  return {
-    sum: sum,
-    product: product,
-  };
+  // Return optimized object syntax: O(1) space
+  return { sum, product };
 }
+
+/*
+ * ORIGINAL IMPLEMENTATION (for comparison):
+ *
+ * export function calculateSumAndProduct(numbers) {
+ *   let sum = 0;
+ *   for (const num of numbers) {    // First pass: O(n)
+ *     sum += num;
+ *   }
+ *
+ *   let product = 1;
+ *   for (const num of numbers) {    // Second pass: O(n)
+ *     product *= num;
+ *   }
+ *
+ *   return {                        // Total: O(2n) = O(n) time
+ *     sum: sum,                     // O(1) space
+ *     product: product,
+ *   };
+ * }
+ *
+ * IMPROVEMENTS MADE:
+ * 1. Reduced from 2n to n operations (50% fewer iterations)
+ * 2. Better cache locality (single pass through memory)
+ * 3. Same O(n) time complexity but with better constant factors
+ */

Sprint-1/JavaScript/findCommonItems/findCommonItems.js

@@ -1,14 +1,46 @@
 /**
  * Finds common items between two arrays.
  *
- * Time Complexity:
- * Space Complexity:
- * Optimal Time Complexity:
+ * Time Complexity: O(n + m) - Single pass through both arrays
+ * Space Complexity: O(min(n, m)) - Set size bounded by smaller array
+ * Optimal Time Complexity: O(n + m) - Cannot do better than linear time
  *
  * @param {Array} firstArray - First array to compare
  * @param {Array} secondArray - Second array to compare
  * @returns {Array} Array containing unique common items
  */
-export const findCommonItems = (firstArray, secondArray) => [
-  ...new Set(firstArray.filter((item) => secondArray.includes(item))),
-];
+export const findCommonItems = (firstArray, secondArray) => {
+  // OPTIMIZED IMPLEMENTATION: O(n + m) time complexity
+  // Previous implementation: O(n × m) due to nested includes() calls
+
+  // Convert second array to Set for O(1) lookup: O(m) time, O(m) space
+  const secondSet = new Set(secondArray);
+
+  // Find common items using Set lookup: O(n) time
+  const commonItems = firstArray.filter((item) => secondSet.has(item));
+
+  // Remove duplicates: O(n) time in worst case
+  return [...new Set(commonItems)];
+};
+
+/*
+ * ORIGINAL IMPLEMENTATION (for comparison):
+ *
+ * export const findCommonItems = (firstArray, secondArray) => [
+ *   ...new Set(firstArray.filter((item) => secondArray.includes(item))),
+ * ];
+ *
+ * COMPLEXITY ANALYSIS OF ORIGINAL:
+ * - firstArray.filter(): O(n) iterations
+ * - secondArray.includes(): O(m) for each iteration
+ * - Total: O(n × m) time complexity
+ * - Space: O(n) for Set creation
+ *
+
+ * IMPROVEMENTS MADE:
+ * 1. Reduced from O(n × m) to O(n + m) time complexity
+ * 2. Set lookup is O(1) vs Array.includes() O(m)
+ * 3. Significant performance gain for large arrays
+ * 4. Same functionality with better algorithmic efficiency
+
+ */

Sprint-1/JavaScript/hasPairWithSum/hasPairWithSum.js

@@ -1,21 +1,59 @@
 /**
  * Find if there is a pair of numbers that sum to a given target value.
  *
- * Time Complexity:
- * Space Complexity:
- * Optimal Time Complexity:
+ * Time Complexity: O(n) - Single pass through the array
+ * Space Complexity: O(n) - Set to store seen numbers
+ * Optimal Time Complexity: O(n) - Cannot do better than linear time
  *
  * @param {Array<number>} numbers - Array of numbers to search through
  * @param {number} target - Target sum to find
  * @returns {boolean} True if pair exists, false otherwise
  */
 export function hasPairWithSum(numbers, target) {
-  for (let i = 0; i < numbers.length; i++) {
-    for (let j = i + 1; j < numbers.length; j++) {
-      if (numbers[i] + numbers[j] === target) {
-        return true;
-      }
+  // OPTIMIZED IMPLEMENTATION: O(n) time complexity
+  // Previous implementation: O(n²) due to nested loops
+
+  const seen = new Set(); // O(n)
+
+  //  O(n) time complexity
+  for (const num of numbers) {
+    const complement = target - num;
+    // O(1) lookup
+    if (seen.has(complement)) {
+      return true;
     }
+
+    //  O(1) operation
+    seen.add(num);
   }
   return false;
 }
+console.log(hasPairWithSum([3, 2, 3, 4, 5], 9));
+/*
+ * ORIGINAL IMPLEMENTATION (for comparison):
+ *
+ * export function hasPairWithSum(numbers, target) {
+ *   for (let i = 0; i < numbers.length; i++) {           // O(n) iterations
+ *     for (let j = i + 1; j < numbers.length; j++) {     // O(n) iterations each
+ *       if (numbers[i] + numbers[j] === target) {       // O(1) comparison
+ *         return true;
+ *       }
+ *     }
+ *   }
+ *   return false;
+ * }
+ *
+ * COMPLEXITY ANALYSIS OF ORIGINAL:
+ * - Outer loop: O(n) iterations
+ * - Inner loop: O(n) iterations for each outer iteration
+ * - Total: O(n²) time complexity
+ * - Space: O(1) - only using loop variables
+ *
+ * PERFORMANCE ISSUES:
+ * - Quadratic time complexity O(n²)
+ *
+ * IMPROVEMENTS MADE:
+ * 1. Reduced from O(n²) to O(n) time complexity
+ * 2. Single pass through array instead of nested loops
+ * 3. Set lookup is O(1) vs nested iteration O(n)
+ */