day 4

src/day04/README.md

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+# 🎄 Advent of Code 2021 - day 4 🎄
+
+## Info
+
+Task description: [link](https://adventofcode.com/2021/day/4)
+
+## Notes
+
+...

src/day04/index.js

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+import run from "aocrunner"
+import { transpose } from "../utils/index.js"
+
+function check(board) {
+  const board2 = transpose(board)
+  for (let i = 0; i < 5; i++) {
+    if (
+      board[i].every((x) => x === null) ||
+      board2[i].every((x) => x === null)
+    ) {
+      return true
+    }
+  }
+  return false
+}
+
+const parseInput = (rawInput) => {
+  const lines = rawInput.trim().split`\n`
+  const calls = lines.shift().split`,`.map(Number)
+  const boards = []
+  while (lines.length > 0) {
+    const nextBoard = []
+    lines.shift() //blank line
+    for (let i = 0; i < 5; i++) {
+      nextBoard[i] = lines.shift().trim().split(/\s+/).map(Number)
+    }
+    boards.push(nextBoard)
+  }
+  return { calls, boards }
+}
+
+const part1 = (rawInput) => {
+  const { calls, boards } = parseInput(rawInput)
+  const marked = []
+  let winningBoard, lastCall
+  outer: for (const call of calls) {
+    lastCall = call
+    for (const board of boards) {
+      for (const row of board) {
+        for (let i = 0; i < 5; i++) {
+          if (row[i] === call) {
+            row[i] = null
+            if (check(board)) {
+              winningBoard = board
+              break outer
+            }
+          }
+        }
+      }
+    }
+  }
+
+  const sum = winningBoard.reduce(
+    (acc, row) => acc + row.reduce((acc2, cell) => acc2 + cell, 0),
+    0,
+  )
+  return sum * lastCall
+}
+
+const part2 = (rawInput) => {
+  const { calls, boards } = parseInput(rawInput)
+  const marked = []
+  let winningSum, lastCall
+  for (const call of calls) {
+    for (const board of boards) {
+      for (const row of board) {
+        for (let i = 0; i < 5; i++) {
+          if (row[i] === call) {
+            row[i] = null
+            if (check(board)) {
+              lastCall = call
+              winningSum = board.reduce(
+                (acc, row) => acc + row.reduce((acc2, cell) => acc2 + cell, 0),
+                0,
+              )
+              board.splice(0, 5)
+            }
+          }
+        }
+      }
+    }
+  }
+
+  return winningSum * lastCall
+}
+
+run({
+  part1: {
+    tests: [
+      {
+        input: `7,4,9,5,11,17,23,2,0,14,21,24,10,16,13,6,15,25,12,22,18,20,8,19,3,26,1
+
+22 13 17 11  0
+ 8  2 23  4 24
+21  9 14 16  7
+ 6 10  3 18  5
+ 1 12 20 15 19
+
+ 3 15  0  2 22
+ 9 18 13 17  5
+19  8  7 25 23
+20 11 10 24  4
+14 21 16 12  6
+
+14 21 17 24  4
+10 16 15  9 19
+18  8 23 26 20
+22 11 13  6  5
+ 2  0 12  3  7`,
+        expected: 4512,
+      },
+    ],
+    solution: part1,
+  },
+  part2: {
+    tests: [
+      {
+        input: `7,4,9,5,11,17,23,2,0,14,21,24,10,16,13,6,15,25,12,22,18,20,8,19,3,26,1
+
+22 13 17 11  0
+ 8  2 23  4 24
+21  9 14 16  7
+ 6 10  3 18  5
+ 1 12 20 15 19
+
+ 3 15  0  2 22
+ 9 18 13 17  5
+19  8  7 25 23
+20 11 10 24  4
+14 21 16 12  6
+
+14 21 17 24  4
+10 16 15  9 19
+18  8 23 26 20
+22 11 13  6  5
+ 2  0 12  3  7`,
+        expected: 1924,
+      },
+    ],
+    solution: part2,
+  },
+  trimTestInputs: true,
+})