binary tree visiting algorithms

binary_tree_roadtrip.js

function Node (name) {
	this.name = name;
	this.left = null;
	this.right = null;
}

function BinaryTree (node) {
	this.node = node;
	
	this.visit = function(fn) {
		return fn(this.node);
	};

	this.insert = function (name) {
		this._insert(this.node, name);
	};

	this._insert = function (node, name) {
		if (name < node.name) {
			node.left 
				? this._insert(node.left, name) 
				: node.left = new Node(name);
		} else if (name > node.name) {
			node.right 
				? this._insert(node.right, name) 
				: node.right = new Node(name);
		}
	};
}

var preOrder = (node) => {
	if (node === null) return [];
	
	return [node.name].concat(preOrder(node.left), preOrder(node.right));
};

var postOrder = (node) => {
	if (node === null) return [];
	
	return postOrder(node.left).concat(postOrder(node.right), [node.name]);
};

var symmetric = (node) => {
	if (node === null) return [];

	return symmetric(node.left).concat([node.name], symmetric(node.right));
};

var r = new Node('R'),
	m = new Node('M'),
	n = new Node('N'),
	a = new Node('A'),
	b = new Node('B'),
	t = new Node('T'),
	o = new Node('O'),
	q = new Node('Q');

r.left = m;
r.right = n;

m.left = a;
a.right = t;
m.right = b;

n.left = o;
n.right = q;

var tree = new BinaryTree(r);

tree.insert('V');

console.log("preOrder:", tree.visit(preOrder));
console.log("postOrder:", tree.visit(postOrder));
console.log("symmetric:", tree.visit(symmetric));