adventofcode/2023/04/part1.js

import * as R from "remeda";

export const slice_and_dice = R.createPipe(
  (l) =>
    l
      .replace(/Card \d+:/, "")
      .split("|")
      .map((segment) => segment.split(" ").filter(R.identity)),
  ([winning, mine]) => {
    let seen = {};
    winning.forEach((n) => (seen[n] = true));
    let got = mine.filter((n) => seen[n]).length;
    return got;
  },
  (n) => (n == 0 ? 0 : Math.pow(2, n - 1))
);

export const get_lines = R.createPipe( (i) => i.split("\n"),
R.compact);

export function solution_1(input) {
  return R.pipe(
    input,
    get_lines,
    R.map(slice_and_dice),
    R.sumBy(R.identity)
  );
}