Initial data commit

Task/Doubly-linked-list-Element-definition/JavaScript/doubly-linked-list-element-definition.js

@@ -0,0 +1,27 @@
+function DoublyLinkedList(value, next, prev) {
+    this._value = value;
+    this._next = next;
+    this._prev = prev;
+}
+// from LinkedList, inherit: value(), next(), traverse(), print()
+DoublyLinkedList.prototype = new LinkedList();
+
+DoublyLinkedList.prototype.prev = function() {
+    if (arguments.length == 1)
+        this._prev = arguments[0];
+    else
+        return this._prev;
+}
+
+function createDoublyLinkedListFromArray(ary) {
+    var node, prev, head = new DoublyLinkedList(ary[0], null, null);
+    prev = head;
+    for (var i = 1; i < ary.length; i++) {
+        node = new DoublyLinkedList(ary[i], null, prev);
+        prev.next(node);
+        prev = node;
+    }
+    return head;
+}
+
+var head = createDoublyLinkedListFromArray([10,20,30,40]);