A Node.js script for Veritasium's riddle (youtu.be/iSNsgj1OCLA)

veritasium.js

const N = 100
const TO_FIND = 42
const BOXES = {}

let iterations = 0
const trail = []

/**
 * @description Return a fresh set of slips on each call.
 */
const generateSlips = () => new Array(N).fill().map((_, idx) => ++idx)

/**
 * @description Assign random ID and remove it from `SLIPS`.
 */
function extractRandomSlip() {
  let randomSlip
  while (true) {
    randomSlip = Math.ceil(Math.random() * N)
    if (SLIPS.includes(randomSlip))
      return SLIPS.splice(SLIPS.indexOf(randomSlip), 1)
    else continue
  }
}

/**
 * @description Recurse to find the desired slip.
 */
function findNext(key, depth = 1) {
  trail.push(key)
  iterations += 1
  if (BOXES[key][0] === 42) return key
  const foundIn = findNext(BOXES[key], depth + 1)
  if (depth > 1) return foundIn
  return {
    iterations,
    trail,
    foundIn,
  }
}

const SLIPS = generateSlips()
for (let i = 1; i <= 100; i++) BOXES[i] = extractRandomSlip()

const result = findNext(TO_FIND)
console.log('Found in box #%d', result.foundIn[0])
console.log('Took %s hops', result.iterations)
console.log(result.trail.join(' -> '))