// Part 1
// ======

function part1(input) {
  const lines = input.split("\n");
  let sum = 0;

  for (const line of lines) {
    const content = line.split(":")[1];
    const winningNums = content.split("|")[0].match(/\d+/g);
    const myNums = content.split("|")[1].match(/\d+/g);

    let cardSum = 0;

    for (const num of winningNums) {
      if (myNums.includes(num)) {
        if (cardSum == 0) {
          cardSum = 1;
        } else {
          cardSum = cardSum * 2;
        }
      }
    }

    sum = sum + cardSum;
  }

  return sum;
}

// Part 2
// ======

function part2(input) {
  let lines = input.split("\n");
  let amount = Array(lines.length).fill(1);

  for (const [i, line] of lines.entries()) {
    const content = line.split(":")[1];
    const winningNums = content.split("|")[0].match(/\d+/g);
    const myNums = content.split("|")[1].match(/\d+/g);

    let cardSum = 0;

    for (const num of winningNums) {
      if (myNums.includes(num)) {
        cardSum += 1;
      }
    }

    for (let j = 1; j <= cardSum; j++) {
      if (i + j >= lines.length) {
        break;
      }
      amount[i + j] += amount[i];
    }
  }

  return lines.reduce((acc, line, i) => {
    return acc + amount[i];
  }, 0);
}