joshua/aoc2024
1
0
Fork 0
mirror of https://github.com/seigler/aoc2024 synced 2025-07-26 00:36:10 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

much cleaner way to look for shapes in grids

Browse source
This commit is contained in:
Joshua Seigler 2024-12-04 23:05:28 -05:00
parent 54dc419f8a
commit 5764869e99
2 changed files with 28 additions and 104 deletions
Download patch file Download diff file Expand all files Collapse all files

6
.aocrunner.json
View file

@ -48,17 +48,17 @@
{
"part1": {
"solved": true,
"result": "2358",
"result": "2143",
"attempts": [
"0"
],
"time": 327.70272
"time": 67.709144
},
"part2": {
"solved": true,
"result": "1737",
"attempts": [],
"time": 201.22507
"time": 182.986319
}
},
{

126
src/day04/index.ts
View file

@ -4,118 +4,42 @@ const parseInput = (rawInput: string) => {
return rawInput.split('\n').map(line => line.split(''))
}
const directions = ["down","right","dl","dr"] as const
type Direction = typeof directions[number]
type Prospect1 = {
letters: string
direction: Direction
next: [number, number]
}
type Coord = Prospect1['next']
const getNext = (dir: Direction, [row, col]: Coord): Coord => {
switch(dir) {
case "down": {return [row+1, col]}
case "right": {return [row, col+1]}
case "dl": {return [row+1, col-1]}
case "dr": {return [row+1, col+1]}
}
}
const part1 = (rawInput: string) => {
const input = parseInput(rawInput)
let total = 0
let prospects: Prospect1[] = []
input.forEach((line, row) => {
line.forEach((letter, col) => {
prospects = prospects.map((prospect) => {
const {
direction,
letters,
next
} = prospect
if (next[0] < row) return null
if (next[0] === row && next[1] === col) {
const nextLetters = letters + letter
if (["XMAS","SAMX"].includes(nextLetters)) {
total += 1
return null
}
if (["XMA","SAM","XM","SA"].includes(nextLetters)) {
return {
letters: nextLetters,
direction: direction,
next: getNext(direction, next)
}
}
}
return prospect
}).filter(prospect => prospect != null)
if ("XMAS".includes(letter)) {
directions.forEach(direction => {
prospects.push({
letters: letter,
direction,
next: getNext(direction, [row, col])
})
})
}
input.forEach((line,r) => {
line.forEach((cell, c) => {
total += [
[[r,c],[r,c+1],[r,c+2],[r,c+3]], // right
[[r,c],[r+1,c+1],[r+2,c+2],[r+3,c+3]], // downright
[[r,c],[r+1,c],[r+2,c],[r+3,c]], // down
[[r,c],[r+1,c-1],[r+2,c-2],[r+3,c-3]], // downleft
].reduce((acc,cur) => /XMAS|SAMX/.test(cur.map(([r,c]) => {
return (input[r] ?? [])[c] ?? "."
}).join('')) ? acc+1:acc, 0)
})
})
return total
}
type Prospect2 = {
letters: string
direction: Direction
next: [number, number]
center: [number, number]
}
const part2 = (rawInput: string) => {
const input = parseInput(rawInput)
let centers = new Map<string, number>()
let prospects: Prospect2[] = []
let total = 0
input.forEach((line, row) => {
line.forEach((letter, col) => {
prospects = prospects.map((prospect) => {
const {
direction,
letters,
next
} = prospect
if (next[0] < row) return null
if (next[0] === row && next[1] === col) {
const nextLetters = letters + letter
if (["MAS","SAM"].includes(nextLetters)) {
const key = prospect.center.join(",")
if (centers.has(key)) { total++ }
centers.set(key, 1)
return null
}
if (["MA","SA"].includes(nextLetters)) {
return {
...prospect,
letters: nextLetters,
next: getNext(direction, next),
}
}
}
return prospect
}).filter(prospect => prospect != null)
if ("XMAS".includes(letter)) {
["dl" as const, "dr" as const].forEach(direction => {
const center = getNext(direction, [row, col])
prospects.push({
letters: letter,
direction,
next: center,
center,
})
})
for (let r = 0; r < input.length -2; r++) {
for (let c = 0; c < input[0].length -2; c++) {
if(/MMASS|SSAMM|MSAMS|SMASM/.test(
[
[r,c],
[r,c+2],
[r+1,c+1],
[r+2,c],
[r+2,c+2]
].map(([r,c]) => input[r][c]).join('')
)) {
total++
}
})
})
}
}
return total
}
@ -165,5 +89,5 @@ MXMXAXMASX`,
solution: part2,
},
trimTestInputs: true,
onlyTests: false,
onlyTests: true,
})