import fs from "node:fs"; const input = fs.readFileSync("inputs/day1").toString(); const sort = (a: number, b: number) => a - b; const lists: number[][] = []; input.split("\n").forEach(line => { line.split(/\s+/g).forEach((i, list) => { lists[list] = lists[list] || []; lists[list].push(Number(i)); }) }) lists.forEach(i => i.sort(sort)); const rows: number[] = []; lists[0].forEach((a) => { rows.push(a * lists[1].filter(b => a === b).length); }) const result = rows.reduce((prev, cur) => prev + cur); console.log(result);