this post was submitted on 01 Dec 2024
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Advent Of Code

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An unofficial home for the advent of code community on programming.dev!

Advent of Code is an annual Advent calendar of small programming puzzles for a variety of skill sets and skill levels that can be solved in any programming language you like.

AoC 2024

Solution Threads

M T W T F S S
1
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25

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console.log('Hello World')

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Day 1: Historian Hysteria

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  • Keep top level comments as only solutions, if you want to say something other than a solution put it in a new post. (replies to comments can be whatever)
  • You can send code in code blocks by using three backticks, the code, and then three backticks or use something such as https://blocks.programming.dev if you prefer sending it through a URL

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[โ€“] [email protected] 1 points 3 weeks ago

JavaScript

After writing a procedural to-the-point version in C, tried a JavaScript solution too because it's just perfect for list comprehension. The part 2 search is inefficient but the data size is small.

Code

const fs = require("fs");
const U = require("./util");

const pairs = fs
    .readFileSync(process.argv[2] || process.stdin.fd, "utf8")
    .split("\n")
    .filter(x => x != "")
    .map(x => x.split(/ +/).map(Number));

const ls = pairs.map(x => x[0]); ls.sort();
const rs = pairs.map(x => x[1]); rs.sort();

const p1 = U.sum(ls.map((l, i) => Math.abs(l - rs[i])));
const p2 = U.sum(ls.map(l => l * U.count(rs, l)));

console.log("01:", p1, p2);

https://github.com/sjmulder/aoc/blob/master/2024/js/day01.js