2025aoc11.js

const input = Object.fromEntries(document.querySelector('pre').innerText.trim().split('\n').map(L => [L.substring(0, 3), L.substring(5).split(' ')]))

function traverse(
    path = ['you'],
    count = {},
    last = path[path.length - 1],
    dac = path.indexOf('dac') >= 0,
    fft = path.indexOf('fft') >= 0,
    key = last + dac + fft
) {
    if (last == 'out') return !!(path[0] === 'you' || dac && fft)
    if (key in count)  return count[key]
    return count[key] = input[last]
        .filter(next => path.indexOf(next) < 0)
        .reduce((acc, next) => acc + traverse([...path, next], count), 0)
}

console.log({ result1: traverse(), result2: traverse(['svr']) })