// Javascript
function mknode(label, adjacent) {
  return { label: label, adjacent: adjacent, baconNumber: -1 };
}

var angelinaJolie = mknode('Angelina Jolie', []),
    bradPitt = mknode('Brad Pitt', []),
    kevinBacon = mknode('Kevin Bacon', []),
    junoTemple = mknode('Juno Temple', []),
    billPaxton = mknode('Bill Paxton', []),
    tomHanks = mknode('Tom Hanks', []),
    noMoviesActor = mknode('No Movies Actor', []);


angelinaJolie.adjacent.push(bradPitt); // Mr and Mrs Smith
angelinaJolie.adjacent.push(junoTemple); // Malificent

bradPitt.adjacent.push(angelinaJolie); // Mr and Mrs Smith
bradPitt.adjacent.push(kevinBacon); // Beyond All Boundaries

kevinBacon.adjacent.push(bradPitt); // Beyond All Boundaries
kevinBacon.adjacent.push(junoTemple); // Black Mass
kevinBacon.adjacent.push(tomHanks); // Apollo 13
kevinBacon.adjacent.push(billPaxton); // Apollo 13

junoTemple.adjacent.push(kevinBacon); // Black Mass
junoTemple.adjacent.push(angelinaJolie); // Malificent

billPaxton.adjacent.push(kevinBacon); // Apollo 13
billPaxton.adjacent.push(tomHanks); // Apollo 13

tomHanks.adjacent.push(kevinBacon); // Apollo 13
tomHanks.adjacent.push(billPaxton); // Apollo 13

function baconNumber(actor) {
  var currentBaconNumber = 0,
      queue = [],
      v = null;

  if (actor.baconNumber !== -1) {
    return actor.baconNumber;
  }

  function enqueueIf(v) {
    if (v.baconNumber === -1) {
      v.baconNumber = currentBaconNumber;
      queue.push(v);
    }
  }

  enqueueIf(kevinBacon);

  while (queue.length) {
    v = queue.shift();

    if (v === actor) {
      return v.baconNumber;
    }

    currentBaconNumber = v.baconNumber + 1;

    v.adjacent.forEach(enqueueIf);
  }

  return -1;
}

console.log(baconNumber(junoTemple));
console.log(baconNumber(bradPitt));
console.log(baconNumber(billPaxton));
console.log(baconNumber(kevinBacon));
console.log(baconNumber(tomHanks));
console.log(baconNumber(noMoviesActor));
console.log(baconNumber(angelinaJolie));