CycleLink.html

<script>
function Node(element) {
    this.element = element;
    this.next = null;
}
function LList() {
	this.head = new Node("head");
	this.head.next = this.head;
}

LList.prototype = {
	find: function(item){
		var currNode = this.head;
        while (currNode.element != item) {
           currNode = currNode.next;
        }
        return currNode;
	},
	insert: function(newElement, item) { 
		var newNode = new Node(newElement); 
		var current = this.find(item); 
		newNode.next = current.next; 
		current.next = newNode;
	},
	display: function(){
		var currNode = this.head;
        while (!(currNode.next == null) && !(currNode.next.element == "head")) {
           document.writeln(currNode.next.element);
           currNode = currNode.next;
        }
	},
	findPrevious: function(item){
		var currNode = this.head;
		while (!(currNode.next == null) && (currNode.next.element != item)) {
			currNode = currNode.next;
		}
		return currNode;
	},
	remove: function(item){
		var prevNode = this.findPrevious(item);
        if (!(prevNode.next == null)) {
            prevNode.next = prevNode.next.next;
        }
	},
	displayNext: function(item){
		var next = this.find(item).next.element;
		document.writeln(next)
	}
}

var cities = new LList();
cities.insert("Conway", "head");
cities.insert("Russellville", "Conway");
cities.insert("Carlisle", "Russellville");
cities.insert("Alma", "Carlisle");
cities.display();
document.write("<br>")
cities.remove("Carlisle");
cities.display();

document.write("<br>");
console.log(cities.displayNext("Alma"))
</script>