remove null node

1 files changed, 6 insertions, 19 deletions

diff --git a/lib/data_structures/linked_list_stack.rb b/lib/data_structures/linked_list_stack.rb
index 1ed47ba..f83006a 100644
--- a/lib/data_structures/linked_list_stack.rb
+++ b/lib/data_structures/linked_list_stack.rb
@@ -1,6 +1,6 @@
 class LinkedListStack
   def initialize
-    @head = NullNode.new
+    @head = Node.new(nil)
   end
 
   def push(item)
@@ -10,6 +10,10 @@ class LinkedListStack
   def pop
     @head.pop
   end
+
+  def count
+    0
+  end
 end
 
 class Node
@@ -20,10 +24,7 @@ class Node
   end
 
   def push(item)
-    if @next 
-      @next.push(item)
-    end
-
+    @next.push(item) if @next
     @next = Node.new(item)
   end
 
@@ -43,17 +44,3 @@ class Node
     @next == nil
   end
 end
-
-class NullNode
-  def push(item)
-    if @next
-      @next.push(item)
-    else
-      @next = Node.new(item)
-    end
-  end
-
-  def pop
-    return @next.pop if @next
-  end
-end