From 52437aeb8aa9f5a94f09976040ca9295cae5e578 Mon Sep 17 00:00:00 2001 From: Joshua Seigler Date: Wed, 11 Dec 2024 01:15:05 -0500 Subject: [PATCH] day 11, cleaner --- .aocrunner.json | 4 ++-- src/day11/index.ts | 51 ++++++++++++++++------------------------------ 2 files changed, 19 insertions(+), 36 deletions(-) diff --git a/.aocrunner.json b/.aocrunner.json index 4d51d06..61e78cf 100644 --- a/.aocrunner.json +++ b/.aocrunner.json @@ -162,7 +162,7 @@ "solved": true, "result": "213625", "attempts": [], - "time": 54.460336 + "time": 4.472301 }, "part2": { "solved": true, @@ -170,7 +170,7 @@ "attempts": [ "299307972" ], - "time": 130.250605 + "time": 126.217947 } }, { diff --git a/src/day11/index.ts b/src/day11/index.ts index 68c0014..1a44764 100644 --- a/src/day11/index.ts +++ b/src/day11/index.ts @@ -2,50 +2,33 @@ import run from "aocrunner" const parseInput = (rawInput: string) => rawInput.split(' ').map(Number) -function cacheKey(...args) { // good enough - return args.map(String).join('\n'); -} -function memoize(fn: (...args: T) => U): (...args: T) => U { - const cache = {}; // Saves the values +const memoize = (fn: (...args: T) => U): (...args: T) => U => { + const cache = {} // Saves the values return (...args) => { - const key = cacheKey(...args); - if (!cache[key]) { // Not in the cache? Call fn. - cache[key] = fn(...args); // Now it's in the cache. - } - return cache[key]; + const key = args.join('\n') + return cache[key] ?? (cache[key] = fn(...args)) } } +/** How many stones will a stone marked `n` be after `turn` blinks? */ +const count = memoize((n: number, turn: number): number => { + if (turn === 0) return 1 + if (n === 0) return count(1, turn - 1) + const digits = Math.floor(Math.log10(n)) + 1 + if (digits % 2 === 0) { + const exp = 10**(digits/2) + return count(Math.floor(n / exp), turn - 1) + count(n % exp, turn - 1) + } + return count(n * 2024, turn - 1) +}) + const part1 = (rawInput: string) => { const input = parseInput(rawInput) - const blink = (n: number, turn: number): number[] => { - if (turn === 0) return [n] - if (n === 0) return blink(1, turn - 1) - const digits = Math.floor(Math.log10(n)) + 1 - if (digits % 2 === 0) { - const exp = 10**(digits/2) - return [ - ...blink(Math.floor(n / exp), turn - 1), - ...blink(n % exp, turn - 1) - ] - } - return blink(n * 2024, turn - 1) - } - return input.flatMap(s => blink(s, 25)).length + return input.reduce((total, s) => total + count(s, 25), 0) } const part2 = (rawInput: string) => { const input = parseInput(rawInput) - const count = memoize((n: number, turn: number): number => { - if (turn === 0) return 1 - if (n === 0) return count(1, turn - 1) - const digits = Math.floor(Math.log10(n)) + 1 - if (digits % 2 === 0) { - const exp = 10**(digits/2) - return count(Math.floor(n / exp), turn - 1) + count(n % exp, turn - 1) - } - return count(n * 2024, turn - 1) - }) return input.reduce((total, s) => total + count(s, 75), 0) }