function Cart() {
	this.items = [0,0,0,0,0];		
}

Cart.prototype.add = function(id) {
	if(this.items[id] == 0)
		this.items[id] = 1;
}

Cart.prototype.remove = function(id) {
	this.items[id] = 0;
}

Cart.prototype.numItems = function() {
	count = 0;
	for(i in this.items)
		count += this.items[i];
	return count;
}

Cart.prototype.total = function() {
	var total = 0;
	for(i = 0; i < this.items.length; i++)
		total += this.items[i] * Products[i].price;
	return total;
}