adventofcode/2023/04/part2.js

import * as R from "remeda";

import { get_lines } from "./part1.js";

export function solution_2(input) {
    const cards = get_lines(input);

    const cards_won = cards.map(()=>1);
    let total_won = 0;

    while( cards.length ) {
    //    console.log(cards_won);
        let card = cards.shift();
        const [ winning, mine  ] = card 
      .replace(/Card \d+:/, "")
      .split("|")
      .map((segment) => segment.split(" ").filter(R.identity));

        let seen = {};
        winning.forEach((n) => (seen[n] = true));
        let got = mine.filter((n) => seen[n]).length;

        R.range(1,got+1).forEach( i => {
            cards_won[i] = (cards_won[i] ?? 0 ) +cards_won[0];
        });

        total_won += cards_won.shift()??0;
    }

    return total_won;
}