Javascript Trees

trees.js

var util = require('util');

function TreeNode(data) {
	this.data = data;
	this.children = [];
}

TreeNode.prototype.isLeaf = function() {
	return this.children.length === 0;
};

TreeNode.prototype.addChild = function(c) {
	this.children.push(c);
};

TreeNode.prototype.show = function() {
	console.log(util.inspect(this, {depth: 20}));
};

TreeNode.prototype.preorder = function() {
	console.log('%s %s', this.data, this.isLeaf());
	this.children.forEach(function(node) {
		node.preorder();
	});
};

TreeNode.prototype.levelorder = function() {
	var q = [];
	q.push(this);

	while (q.length > 0) {
		var node = q.shift();
		console.log('%s %s', node.data, node.isLeaf());
		node.children.forEach(function(c) {
			q.push(c);
		});
	}
};

//          1
//         / \
//        /   \
//       /     \
//      2       3
//     / \     /
//    4   5   6
//   /       /|\
//  7       / | \
//         8  9 10

var one = new TreeNode(1);
var two = new TreeNode(2);
var three = new TreeNode(3);
var four = new TreeNode(4);
var five = new TreeNode(5);
var six = new TreeNode(6);
var seven = new TreeNode(7);
var eight = new TreeNode(8);
var nine = new TreeNode(9);
var ten = new TreeNode(10);

one.addChild(two);
one.addChild(three);

two.addChild(four);
two.addChild(five);

four.addChild(seven);

three.addChild(six);

six.addChild(eight);
six.addChild(nine);
six.addChild(ten);

one.show();

console.log('Depth first, preorder:');
one.preorder();
console.log('Bredth first, level-order:');
one.levelorder();