Given a large hash table whose keys are movie names and whose values are a list of actors in those movies, write a function to determine the Bacon number of a particular actor.

baconTree.js

var assert = require("assert"),
	_ = require("underscore"),
	testData = {
	"Iron Man": ["Robert Downey Jr", "Gwyneth Paltrow", "Terrence Howard"],
	"Iron Man 3": ["Robert Downey Jr", "Guy Pearce", "Gwyneth Paltrow"],
	"Super Troopers": ["Jay Chandrasekhar", "Kevin Heffernan"],
	"The Day After Tomorrow": ["Dennis Quaid", "Jake Gyllenhaal", "Emmy Rossum"],
	"The Phantom of the Opera": ["Gerard Butler", "Emmy Rossum", "Patrick Wilson"],
	"How I Met Your Mother": ['Josh Radnor', "Jason Segel", "Cobie Smulders", "Kevin Heffernan"],
	"Despicable Me": ['Steve Carell', 'Jason Segel', 'Russel Brand', "Michael Fassbender"],
	"The Nightmare Before Christmas": ["Danny Elfman", "Chris Sarandon", "Catherine O'Hara"],
	"Homeland": ["Claire Danes", "Damian Lewis", "Morena Baccarin", "Mandy Patinkin"],
	"Memento": ["Guy Pearce", "Carrie-Anne Moss", "Joe Pantoliano"],
	"The Matrix": ["Keanu Reeves", "Laurence Fishburne", "Carrie-Anne Moss"],
	"The Fugitive": ["Harrison Ford", "Tommy Lee Jones", "Sela Ward"],
	"The Lord of the Rings: The Fellowship of the Ring": ["Elijah Wood", "Ian McKellen", "Orlando Bloom"],
	"The Curious Case of Benjamin Button": ["Brad Pitt", "Cate Blanchett", "Tilda Swinton"],
	"Se7en": ["Morgan Freeman", "Brad Pitt", "Gwyneth Paltrow"],
	"X-Men: First Class": ["James McAvoy", "Michael Fassbender", "Jennifer Lawrence", "Kevin Bacon"],
	"The Hunger Games": ["Jennifer Lawrence", "Josh Hutcherson", "Liam Hemsworth"],
	"The Expendables": ["Sylvester Stalone", "Arnold Swartzenhigger"],
	"The Expendables 2": ["Sylvester Stalone", "Liam Hemsworth", "Randy Couture"],
	"Paranoia": ["Liam Hemsworth", "Gary Oldman", "Harrison Ford"],
	// "Test Movie": ["Sela Ward", "Gerard Butler", "Terrence Howard"],
	// "Test Two": ["Morgan Freeman", "Ian McKellen"]
}

function generateTree(data, rootName) {
	var tree = [rootName, []];
	return generateSubTree([tree], [], data, tree);
}

function generateSubTree(currentQueue, backupQueue, data, treeRoot) {
	var childrenArr = [], thisNode;
	if (currentQueue.length > 0) {
		thisNode = currentQueue.pop();
		childrenArr = _.reject(levelOneActors(data, thisNode[0]),//take out the names that are elsewhere (higher) in the tree
		function (name) {
			return findDepthInTree(treeRoot, name) > -1;
		});
		for (var m = 0; m < childrenArr.length; m++) {
			var childNode = [childrenArr[m], []];
			thisNode[1].push(childNode);
			backupQueue.push(childNode);
		}
		return generateSubTree(currentQueue, backupQueue, data, treeRoot);
	} else if (backupQueue.length > 0) {
		return generateSubTree(backupQueue, [], data, treeRoot);
	} else {
		return treeRoot;
	}
}

function findDepthInTree(tree, name,	depth) {
	//returns numerical depth in tree. root is 0
	var depth = depth || 0;
	if (tree[0] === name) {
		return depth;
	} else {
		for(var m = 0; m < tree[1].length; m++) {
			var branchFind = findDepthInTree(tree[1][m], name, depth + 1);
			if (branchFind != -1) {
				return branchFind;
			}
		}
		return -1;
	}
}

function levelOneActors(data, actorName) {
	return _.reject(
		_.reduce(data, function (accum, actorsArr, movieName) {
		// console.log([actorName, actorsArr.indexOf(actorName), actorsArr].join(" "));
		if (actorsArr.indexOf(actorName) > -1) {
			return accum.concat(actorsArr);
		}
		return accum;
	}, []), rejectActor(actorName)) || [];
}

function rejectActor(rejectName) {
	return function (name) {
		return name === rejectName;
	};
}

var kevinTree = generateTree(testData, "Kevin Bacon");
console.log(JSON.stringify(kevinTree));
var person = "Elijah Wood";
console.log("Bacon Number of " + findDepthInTree(kevinTree, person) + " for " + person); 
var testTree = ["Kevin Bacon", [
	["Marc Martino", [
		["Scott Miller", []],
		["Christian P", []]	]],
	["Kevin Stratton", []]	]];
assert.equal(findDepthInTree(testTree, "Kevin Bacon"), 0, "root found");
assert.equal(findDepthInTree(testTree, "Marc Martino"), 1, "one level down found");
assert.equal(findDepthInTree(testTree, "Christian P"), 2, "two level down on the right found");
assert.equal(findDepthInTree(testTree, "Broccoli Rob"), -1, "no elment found");