feat: day 5 print queue 20241205

README.md

@@ -11,6 +11,7 @@ This repository contains solutions and a local development environment for the [
 - Day 2: Red-Nosed Reports [[link]](/src/2024/2024-12-02/README.md)
 - 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)
 
 </details>
 

src/2024/2024-12-05/README.md

@@ -0,0 +1,14 @@
+## Day 5: Print Queue
+
+Visit the Advent of Code website for more information on this puzzle at:
+
+**Source:** https://adventofcode.com/2024/day/5<br>
+**Status:** Complete ⭐⭐
+
+<br>
+
+| Code | Description |
+| --- | --- |
+| **orderedUpdates.ts** | Has functions for finding correct "updates" according to defined "rules." It also counts the sum of middle page numbers from correctly-ordered "updates." |
+| **fixOrderingUpdates.ts** | Has functions for correcting incorrectly placed "updates" before calculating the sum of the corrected middle page numbers.  |
+| **fileReader.ts** | Reads and transforms a text file for processing by the quiz scripts. |

src/2024/2024-12-05/input.txt

@@ -0,0 +1,28 @@
+39|89
+101|15
+101|95
+101|39
+5|48
+95|15
+5|89
+48|15
+101|48
+89|48
+95|89
+101|89
+95|48
+39|15
+5|39
+101|5
+39|95
+5|95
+39|48
+5|15
+89|15
+
+5,39,95,89,48
+101,95,89,48,15
+5,48,15
+5,101,39,95,89
+95,15,48
+101,15,5,48,39

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

@@ -0,0 +1,56 @@
+import path from 'path'
+import { currentDirectory, readFile } from '@/utils/file.js'
+import { uniformArrayElements } from '@/utils/arrays.js'
+
+export type Rules = Record<number, number[]>
+
+export type QuizData = {
+  rules: Rules;
+  updates: number[][]
+}
+
+/**
+ * Reads and transforms quiz input text for processing.
+ * @param fileName {string} Filename of input text relative to the calling function
+ * @returns {QuizData} Formatted data
+ */
+export const fileReader = (fileName: string): QuizData => {
+  const directory = currentDirectory(import.meta.url)
+  const file = readFile(path.join(directory, '..', fileName))
+
+  const segments = file.split('\n\n')
+
+  if (
+    segments[0] === undefined ||  // rules
+    segments[1] === undefined     // updates
+  ) {
+    throw new Error('Undefined rules or updates data')
+  }
+
+  const rules: Rules = segments[0]
+    .split('\n')
+    .reduce((list: Rules, item) => {
+      const pair: number[] = item.split('|').map(Number)
+
+      if (!uniformArrayElements(pair, 'number')) {
+        throw new Error('Invalid rules value')
+      }
+
+      const key = pair[0] as number
+
+      if (list[key] === undefined) {
+        list[key] = [pair[1] as number]
+      } else {
+        list[key].push(pair[1] as number)
+      }
+
+      return list
+    }, {})
+
+  return {
+    rules,
+    updates: segments[1]
+      .split('\n')
+      .map(item => item.split(',').map(Number))
+  }
+}

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

@@ -0,0 +1,116 @@
+import { isOrderedReport } from './orderedUpdates.js'
+import { arrayMiddleIndex, uniformArrayElements } from '@/utils/arrays.js'
+
+import type { Rules } from './fileReader.js'
+import type { QuizData } from './fileReader.js'
+
+type CurrentItem = {
+  value: number;
+  index: number;
+}
+
+/**
+ * Finds the next appropriate array index to swap places with the incorrectly placed current item accoring 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
+ * @returns {number} Array index to swap positions with the current item
+ */
+const nextHotSwapIndex = (rules: Rules, restItems: number[], currentItem: CurrentItem): number => {
+  let indexToSwap = -1
+
+  for (let i = currentItem.index; i < restItems.length; i += 1) {
+    if (rules[restItems[i] as number]?.includes(currentItem.value)) {
+      indexToSwap = i
+      break
+    }
+  }
+
+  if (indexToSwap === -1) {
+    throw new Error('No array item to swap with')
+  }
+
+  return indexToSwap
+}
+
+/**
+ * Fixes the ordering of an incorrectly-ordered "update" (row) by swapping its elements with target items.
+ * @param rules {Rules} Object containing parsed and formatted rules and updates data
+ * @param unorderedItems {number[]} "updates" array items content
+ * @returns {number[]} Corrected "update" items
+ */
+export const fixOrdering = (rules: Rules, unorderedItems: number[]): number[] => {
+  if (!uniformArrayElements(unorderedItems, '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 }
+
+    // Swaps incorrectly placed items with target items in the array
+    const swapItems = () => {
+      const indexToSwap = nextHotSwapIndex(
+        rules,
+        unorderedItems,
+        currentItemData
+      )
+
+      const temp = unorderedItems[indexToSwap] as number
+      unorderedItems[indexToSwap] = currentItem
+      unorderedItems[i] = temp
+      currentItem = temp
+
+      fixOrdering(rules, unorderedItems)
+    }
+
+    // Correct "update" item should have en entry in the "rules" object
+    // Swap places with other items if its incorrect
+    if (rules[currentItem] === undefined) {
+      swapItems()
+    }
+
+    // Get the rest of items after the current item for comparison
+    const afterItems = unorderedItems.filter((_, index) => index > i)
+
+    // 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()
+    }
+  }
+
+  return [...unorderedItems]
+}
+
+/**
+ * Fixes incorrectly-ordered "updates" and calculates their middle page numbers after fixing.
+ * @param data {QuizData} Object containing "rules" and "updates" input
+ * @param verbose {boolean} Flag to display processing log messages. Defaults to false.
+ * @returns {number} Total middle page numbers from corrected "updates"
+ */
+export const fixOrderingUpdates = (data: QuizData, verbose: boolean = false): number => {
+  let sum = 0
+
+  for (let i = 0; i < data.updates.length; i += 1) {
+    const isOrdered = isOrderedReport(data.rules, data.updates[i] ?? [])
+
+    if (!isOrdered) {
+      const corrected = fixOrdering(
+        data.rules,
+        [...data.updates[i] as number[]]
+      )
+
+      if (verbose) {
+        console.log('---incorrect', data.updates[i])
+        console.log('---corrected', corrected)
+      }
+
+      const middleIndex = arrayMiddleIndex(corrected)
+      const item = corrected[middleIndex - 1]
+      sum += item ?? 0
+    }
+  }
+
+  return sum
+}

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

@@ -0,0 +1,63 @@
+import type { QuizData, Rules } from './fileReader.js'
+import { uniformArrayElements, arrayMiddleIndex } from '@/utils/arrays.js'
+
+/**
+ * Checks if an "update" list is correct according to defined "rules"
+ * @param rules {Rules} Object containing parsed and formatted rules and updates data
+ * @param updateItems {number[]} "updates" array items content
+ * @returns Flag indicating if the set of `updateItems` is correct
+ */
+export const isOrderedReport = (rules: Rules, updateItems: number[]): boolean => {
+  let isOrdered = true
+
+  if (!uniformArrayElements(updateItems, 'number')) {
+    throw new Error('Invalid updateItems item/s')
+  }
+
+  for (let i = 0; i < updateItems.length - 1; i += 1) {
+    const currentItem = updateItems[i] as number
+
+    // Current "update" item should have en entry in the "rules" object
+    if (rules[currentItem] === undefined) {
+      isOrdered = false
+      break
+    }
+
+    // Get the rest of items after the current item for comparison
+    const afterItems = updateItems.filter((_, index) => index > i)
+
+    // Current item's "rule" should have the after-item entries
+    if (!afterItems.every(item => rules[currentItem]?.includes(item))) {
+      isOrdered = false
+      break
+    }
+  }
+
+  return isOrdered
+}
+
+/**
+ * Counts the sum of middle page numbers from correctly-ordered "updates"
+ * @param data {QuizData} Object containing "rules" and "updates" input
+ * @param verbose {boolean} Flag to display processing log messages. Defaults to false.
+ * @returns {number} Total middle page numbers from correct "updates"
+ */
+export const sumOfCorrectUpdates = (data: QuizData, verbose: boolean = false): number => {
+  let sum = 0
+
+  for (let i = 0; i < data.updates.length; i += 1) {
+    const isOrdered = isOrderedReport(data.rules, data.updates[i] ?? [])
+
+    if (isOrdered) {
+      if (verbose) {
+        console.log('---correct', data.updates[i])
+      }
+
+      const mid = arrayMiddleIndex(data.updates[i] as number[])
+      const item = data.updates[i]?.[mid - 1]
+      sum += item ?? 0
+    }
+  }
+
+  return sum
+}

src/2024/2024-12-05/main.ts

@@ -0,0 +1,29 @@
+import { fileReader } from './lib/fileReader.js'
+import type { QuizData } from './lib/fileReader.js'
+
+import { sumOfCorrectUpdates } from './lib/orderedUpdates.js'
+import { fixOrderingUpdates } from './lib/fixOrderingUpdates.js'
+
+const data: QuizData = fileReader('input.txt')
+
+/**
+ * Part 1/2 of the 2024-12-05 quiz
+ * Counts the sum of middle pages from correct updates
+ */
+const quiz20241205_01 = () => {
+  const sum = sumOfCorrectUpdates(data, true)
+  console.log('Sum of middle page numbers:', sum)
+}
+
+/**
+ * Part 2/2 of the 2024-12-05 quiz
+ * Fixes incorrectly-ordered updates and counts
+ *  the sum of middle pages from corrected updates
+ */
+const quiz20241205_02 = () => {
+  const sum = fixOrderingUpdates(data, true)
+  console.log('Sum of corrected middle page numbers:', sum)
+}
+
+quiz20241205_01()
+quiz20241205_02()

src/2024/2024-12-05/sample.test.ts

@@ -0,0 +1,16 @@
+import { test, expect } from 'vitest'
+import { fileReader } from './lib/fileReader.js'
+import type { QuizData } from './lib/fileReader.js'
+
+import { sumOfCorrectUpdates } from './lib/orderedUpdates.js'
+import { fixOrderingUpdates } from './lib/fixOrderingUpdates.js'
+
+const data: QuizData = fileReader('input.txt')
+
+test('Count middle pages - demo', () => {
+  expect(sumOfCorrectUpdates(data)).toBe(232)
+})
+
+test('Fix ordering - demo', () => {
+  expect(fixOrderingUpdates(data)).toBe(126)
+})

src/index.ts

@@ -4,3 +4,15 @@ export { similarityScore } from './2024/2024-12-01/lib/similarityScore.js'
 export { countSafeReports } from './2024/2024-12-02/lib/countSafeReports.js'
 export { extractMultiply } from './2024/2024-12-03/lib/extractMultiply.js'
 export { extractMultiplyCondition } from './2024/2024-12-03/lib/extractMultiply.js'
+export { wordCount } from './2024/2024-12-04/lib/wordCount.js'
+
+export {
+  checkDiagonal,
+  checkHorizontal,
+  checkVertical
+} from './2024/2024-12-04/lib/wordCheckerUtils.js'
+
+export { isOrderedReport } from './2024/2024-12-05/lib/orderedUpdates.js'
+export { sumOfCorrectUpdates } from './2024/2024-12-05/lib/orderedUpdates.js'
+export { fixOrderingUpdates } from './2024/2024-12-05/lib/fixOrderingUpdates.js'
+export { fixOrdering } from './2024/2024-12-05/lib/fixOrderingUpdates.js'

src/utils/arrays.ts

@@ -18,3 +18,24 @@ export const arrangeArray = (order: ARRAY_ORDERING) =>
       throw new Error('Invalid ordering')
     }
   }
+
+/**
+ * Checks if array elements have the same type and has no null or undefined values
+ * @param items {S[]} array of elements
+ * @param type {T} type name of the elements inside the `items` array
+ * @returns {boolean} Flag indicating if all array elements have the same type
+ */
+export const uniformArrayElements = <S, T>(items: S[], type: T): boolean => {
+  return (
+    items.filter(value => typeof value === type).length === items.length
+  )
+}
+
+/**
+ * Retrieves the middle (center) index of an array
+ * @param list {T[]} 1-dimensional array
+ * @returns {number} Middle index of an array
+ */
+export const arrayMiddleIndex = <T>(list: T[]): number => {
+  return Math.floor(list.length / 2) + list.length % 2
+}