v1.2.1

.gitignore

@@ -5,3 +5,7 @@ dist/
 *.zip
 *.rar
 *.tgz
+src/**/*.js
+
+**/*.txt
+!src/**/*.txt

.npmrc

@@ -0,0 +1 @@
+engine-strict=true

.nvmrc

@@ -0,0 +1 @@
+20.15.0

README.md

@@ -1,6 +1,8 @@
 ## ✨ adventofcode
 
-This repository contains solutions and a local development environment for the [Advent of Code](https://adventofcode.com/) event puzzles.
+This repository contains solutions and a local development environment for the [Advent of Code](https://adventofcode.com/) event puzzles using TypeScript/JavaScript.
+
+The codes are structured in a way that discusses and walks through the solution steps for the AoC quizzes rather than focusing on AoC's competitive programming.
 
 ### 🎄 Advent of Code Quiz Information
 
@@ -12,6 +14,11 @@ This repository contains solutions and a local development environment for the [
 - Day 3: Mull It Over [[link]](/src/2024/2024-12-03/README.md)
 - Day 4: Ceres Search [[link]](/src/2024/2024-12-04/README.md)
 - Day 5: Print Queue [[link]](/src/2024/2024-12-05/README.md)
+- Day 6: Guard Gallivant [[link]](/src/2024/2024-12-06/README.md)
+- Day 7: Bridge Repair [[link]](/src/2024/2024-12-07/README.md)
+- Day 8: Resonant Collinearity [[link]](/src/2024/2024-12-08/README.md)
+- Day 9: Disk Fragmenter [[link]](/src/2024/2024-12-09/README.md)
+- Day 10: Hoof It [[link]](/src/2024/2024-12-10/README.md)
 
 </details>
 
@@ -72,7 +79,7 @@ Each Advent of Code (AOC) event quiz has its folder under **`"/src/<YEAR>/<YYYY-
 
 ### 📋 Requirements
 
-- Node v20.15.0
+- Node v20.15.0 (at least)
    - node: 20.15.0
    - npm: 10.7.0
 
@@ -95,7 +102,7 @@ Each Advent of Code (AOC) event quiz has its folder under **`"/src/<YEAR>/<YYYY-
 Using Node
 
 1. (Optional) Replace the values of specific `input.txt` in the `"/src/<YEAR>/<YYYY-MM-DD>"` directories with actual AOC input.
-2. Run a non-test TypeScript file inside the **/src** directory. For example:
+2. Run a non-test TypeScript file inside the **/src** directory from the project's _**"root directory"**_. For example:
    ```
    npx vite-node src/sample/sample.ts
    ```
@@ -108,7 +115,7 @@ Using Node
    npm run transpile
    node dist/sample/sample.js
    ```
-4. See the [Available Scripts](#available-scripts) section for more information.
+4. See the [Available Scripts](#-available-scripts) section for more information.
 
 ## ⚡ Alternate Usage
 

package.json

@@ -5,8 +5,8 @@
   "main": "dist/index.js",
   "type": "module",
   "engines": {
-    "node": "20.15.0",
-    "npm": "10.7.0"
+    "node": ">=20.15.0",
+    "npm": ">=10.7.0"
   },
   "scripts": {
     "dev": "vitest",

src/2024/2024-12-01/lib/fileReader.ts

@@ -1,5 +1,5 @@
 import path from 'path'
-import { readFile, currentDirectory } from '@/utils/file.js'
+import { readFile, directory } from '@/utils/file.js'
 
 export type arrayLists = {
   list1: string[];
@@ -12,8 +12,8 @@ export type arrayLists = {
  */
 export const fileReader = (): arrayLists => {
   // Read quiz input file
-  const directory = currentDirectory(import.meta.url)
-  const file = readFile(path.join(directory, '..', 'input.txt'))
+  const dir = directory(import.meta.url)
+  const file = readFile(path.join(dir, '..', 'input.txt'))
   const pairs: string[] = file.split('\n')
 
   const list1: string[] = []

src/2024/2024-12-02/lib/fileReader.ts

@@ -1,14 +1,14 @@
 import path from 'path'
-import { readFile, currentDirectory } from '@/utils/file.js'
+import { readFile, directory } from '@/utils/file.js'
 
 /**
  * Reads the quiz's input file into two (2) string arrays
  * @returns {arrayLists} An object containing two (2) string arrays: `{ list1, list2 }`
  */
 export const fileReader = (): number[][] => {
   // Read quiz input file
-  const directory = currentDirectory(import.meta.url)
-  const file = readFile(path.join(directory, '..', 'input.txt'))
+  const dir = directory(import.meta.url)
+  const file = readFile(path.join(dir, '..', 'input.txt'))
 
   return file
     .split('\n')

src/2024/2024-12-03/main.ts

@@ -1,9 +1,9 @@
 import path from 'path'
-import { currentDirectory, readFile } from '@/utils/file.js'
+import { directory, readFile } from '@/utils/file.js'
 import { extractMultiply, extractMultiplyCondition } from './lib/extractMultiply.js'
 
-const directory = currentDirectory(import.meta.url)
-const input = readFile(path.join(directory, 'input.txt'))
+const dir = directory(import.meta.url)
+const input = readFile(path.join(dir, 'input.txt'))
 
 /**
  * Part 1/2 of the 2024-12-03 quiz

src/2024/2024-12-04/main.ts

@@ -1,11 +1,11 @@
 import path from 'path'
-import { currentDirectory, readFile } from '@/utils/file.js'
+import { directory, readFile } from '@/utils/file.js'
 import { wordCount } from './lib/wordCount.js'
 import { countMASword } from './lib/xmasCount.js'
 
-const directory = currentDirectory(import.meta.url)
+const dir = directory(import.meta.url)
 
-const data: string[][] = readFile(path.join(directory, 'input.txt'))
+const data: string[][] = readFile(path.join(dir, 'input.txt'))
   .split('\n')
   .map(row => row.split(''))
 

src/2024/2024-12-05/lib/fileReader.ts

@@ -1,5 +1,5 @@
 import path from 'path'
-import { currentDirectory, readFile } from '@/utils/file.js'
+import { directory, readFile } from '@/utils/file.js'
 import { uniformArrayElements } from '@/utils/arrays.js'
 
 export type Rules = Record<number, number[]>
@@ -15,8 +15,8 @@ export type QuizData = {
  * @returns {QuizData} Formatted data
  */
 export const fileReader = (fileName: string): QuizData => {
-  const directory = currentDirectory(import.meta.url)
-  const file = readFile(path.join(directory, '..', fileName))
+  const fir = directory(import.meta.url)
+  const file = readFile(path.join(fir, '..', fileName))
 
   const segments = file.split('\n\n')
 

src/2024/2024-12-05/lib/fixOrderingUpdates.ts

@@ -10,7 +10,7 @@ type CurrentItem = {
 }
 
 /**
- * Finds the next appropriate array index to swap places with the incorrectly placed current item accoring to the "rules"
+ * Finds the next appropriate array index to swap places with the incorrectly placed current item according to the "rules"
  * @param rules {Rules} Object containing parsed and formatted rules and updates data
  * @param restItems {number[]} "updates" array items content
  * @param currentItem {CurrentItem} Object containing the "current" item data in focus: value and array index
@@ -44,30 +44,32 @@ export const fixOrdering = (rules: Rules, unorderedItems: number[]): number[] =>
     throw new Error('Invalid item/s')
   }
 
-  for (let i = 0; i < unorderedItems.length - 1; i += 1) {
-    let currentItem = unorderedItems[i] as number
-    const currentItemData = { value: currentItem, index: i }
+  let currentItem: number = -2
 
-    // Swaps incorrectly placed items with target items in the array
-    const swapItems = () => {
-      const indexToSwap = nextHotSwapIndex(
-        rules,
-        unorderedItems,
-        currentItemData
-      )
+  // Swaps incorrectly placed items with target items in the array
+  const swapItems = (activeItem: CurrentItem, activeIndex: number) => {
+    const indexToSwap = nextHotSwapIndex(
+      rules,
+      unorderedItems,
+      activeItem
+    )
 
-      const temp = unorderedItems[indexToSwap] as number
-      unorderedItems[indexToSwap] = currentItem
-      unorderedItems[i] = temp
-      currentItem = temp
+    const temp = unorderedItems[indexToSwap] as number
+    unorderedItems[indexToSwap] = activeItem.value
+    unorderedItems[activeIndex] = temp
+    currentItem = temp
 
-      fixOrdering(rules, unorderedItems)
-    }
+    fixOrdering(rules, unorderedItems)
+  }
+
+  for (let i = 0; i < unorderedItems.length - 1; i += 1) {
+    currentItem = unorderedItems[i] as number
+    const currentItemData = { value: currentItem, index: i }
 
     // Correct "update" item should have en entry in the "rules" object
     // Swap places with other items if its incorrect
     if (rules[currentItem] === undefined) {
-      swapItems()
+      swapItems(currentItemData, i)
     }
 
     // Get the rest of items after the current item for comparison
@@ -76,7 +78,7 @@ export const fixOrdering = (rules: Rules, unorderedItems: number[]): number[] =>
     // Correct item's "rule" should have the after-item entries
     // Swap places with other items if its incorrect
     if (!afterItems.every(item => rules[currentItem]?.includes(item))) {
-      swapItems()
+      swapItems(currentItemData, i)
     }
   }
 

src/2024/2024-12-06/README.md

@@ -0,0 +1,25 @@
+## Day 6: Guard Gallivant
+
+Visit the Advent of Code website for more information on this puzzle at:
+
+**Source:** https://adventofcode.com/2024/day/6<br>
+**Status:** Complete ⭐⭐
+
+## Code
+
+1. **grid.ts**
+   - `Grid` - class that has a 2D array object containing paths and obstacles in which a `Guard` runs.
+   - Has functions and methods for managing a `Grid` object
+
+2. **guard.ts**
+   - `Guard` - class representing an object that can walk in the `Grid` map.
+   - Have methods for moving around in the `Grid`.
+
+3. **guardController.ts**
+   - `guardController()` - Runs the `Guard` on the `Grid`, counting distinct positions/steps.
+
+5. **guardControllerLoop.ts**
+   - `gridHasInfiniteLoop()`
+      - Runs the `Guard` on a `Grid` with obstacles, checking the placement of paths and obstacles that will make the `Guard` walk in an infinite loop
+   - `findObstructionPositions()` - Counts the number of positions in the `Grid` in which inserting one (1) obstruction symbol # will cause the `Guard` to walk in an infinite loop.
+      - > _**WARNING:** This is a very slow, unoptimized program execution that takes about ~3 mins to complete using the actual AoC input text._

src/2024/2024-12-06/input.txt

@@ -0,0 +1,10 @@
+....#.....
+.........#
+..........
+.#........
+..........
+.......#..
+.#..^.....
+.#......#.
+....#.....
+......#...

src/2024/2024-12-06/lib/grid.ts

@@ -0,0 +1,126 @@
+import { GuardStatus, GuardDirection } from './guard.types.js'
+import type { GuardState } from './guard.types.js'
+
+
+/**
+ * @class Grid
+ * @description Object containing a 2D array of strings and other data in which a `Guard` object runs. Each item represents an open path or obstacle.
+ */
+export class Grid {
+  /** 2D board string array */
+  board: string[][] = []
+
+  /** Board length */
+  length: number = 0
+
+  /** Board width */
+  width: number = 0
+
+  /** Number of distinct positions that a `Guard` can traverse on the board */
+  positionCount: number = 0
+
+  /** Initial (x,y) coordinate starting position of a `Guard` */
+  start: { x: number; y: number; }
+
+  /** Obstruction symbol. Guards turn clockwise if this symbol blocks their next step. */
+  obstruction = '#'
+
+  /** Path symbol. Guards proceed to the next (x,y) coordinate after on this symbol. */
+  pathSymbol = '.'
+
+  /**
+   * @constructor
+   * @param {string[][]} data 2D string array containing paths `"."`, obstacles `"#"` and the `Guard` object
+   * @param obstructionSymbol
+   */
+  constructor (data: string[][], obstructionSymbol: string = '#') {
+    this.board = data
+    this.length = data.length
+    this.width = (data[0])?.length as number
+    this.obstruction = obstructionSymbol
+    this.start = { x: -1, y: -1 }
+
+    this.findGuardStartPosition()
+  }
+
+  /**
+   * Finds the initial position and state of the guard in a 2D board array
+   * @param data {string[][]} 2D string array of the guard board
+   * @returns {GuardState} Initial position and state of the guard
+   */
+  findGuardStartPosition (): GuardState {
+    const GuardDirections: string[] = Object.values(GuardDirection)
+
+    const initialState: GuardState = {
+      direction: null,
+      xPos: -1,
+      yPos: -1,
+      status: GuardStatus.IDLE
+    }
+
+    for (let y = 0; y < this.board.length; y += 1) {
+      const row = this.board[y]
+
+      if (row === undefined) {
+        throw new Error('Undefined row')
+      }
+
+      for (let i = 0; i < GuardDirections.length; i += 1) {
+        const indexOfDirection = row.indexOf(GuardDirections[i] as string)
+
+        if (indexOfDirection >= 0) {
+          initialState.direction = GuardDirections[i] as GuardDirection
+          initialState.xPos = indexOfDirection
+          initialState.yPos = y
+          initialState.status = GuardStatus.ACTIVE
+          break
+        }
+      }
+
+      if (initialState.status === GuardStatus.ACTIVE) break
+    }
+
+    this.start.x = initialState.xPos
+    this.start.y = initialState.yPos
+
+    return initialState
+  }
+
+  /**
+   * Checks if an (x,y) coordinate is outside the grid area
+   * @param {number} x array x coordinate
+   * @param {number} y array y coordinate
+   * @returns {boolean} Flag indicating if the guard is outside the grid
+   */
+  isOutOfBounds (x: number, y: number): boolean {
+    const row = this.board[0] as string[]
+
+    return x < 0 ||
+      x >= row.length ||
+      y < 0 ||
+      y >= this.board.length
+  }
+
+  /**
+   * Marks an (x,y) coordinate in the grid
+   * @param {number} x array x coordinate
+   * @param {number} y array y coordinate
+   * @returns {void}
+   */
+  mark (x: number, y: number): void {
+    const row = this.board[y]
+
+    if (row !== undefined && row[x] !== 'X') {
+      row[x] = 'X'
+      this.positionCount += 1
+    }
+  }
+
+  /**
+   * Displays the guard's distinct positions in the grid
+   */
+  print () {
+    console.clear()
+    console.log(this.board.map(row => row.join(' ')))
+  }
+}