0
@@ -13,33 +13,32 @@ class IntervalSkipList
0
   end
0
 
0
   def expire(range, length_change)
0
-    markers, start_node = containing(range.first)
0
-
0
-    markers.each do |marker|
0
+    expired_markers, first_node_after_range = overlapping(range)
0
+    expired_markers.each do |marker|
0
       delete(marker)
0
     end
0
 
0
-    cur_node = start_node
0
+    cur_node = first_node_after_range
0
     while cur_node do
0
       cur_node.key += length_change if cur_node.key >= range.last
0
       cur_node = cur_node.forward[0]
0
     end
0
   end
0
 
0
+  def overlapping(range)
0
+    markers, first_node = containing_with_node(range.first)
0
+    cur_node = first_node
0
+
0
+    begin
0
+      markers.concat(cur_node.forward_markers.flatten)
0
+      cur_node = cur_node.forward[0]
0
+    end while cur_node.key < range.last
0
+
0
+    return markers.uniq, cur_node
0
+  end
0
+
0
   def containing(n)
0
-    containing = []
0
-    cur_node = head
0
-    (max_height - 1).downto(0) do |cur_level|
0
-      while (next_node = cur_node.forward[cur_level]) && next_node.key <= n
0
-        cur_node = next_node
0
-        if cur_node.key == n
0
-          return containing + (cur_node.markers - cur_node.endpoint_of), cur_node
0
-        end
0
-      end
0
-      containing.concat(cur_node.forward_markers[cur_level])
0
-    end
0
-    
0
-    return containing, cur_node
0
+    containing_with_node(n).first
0
   end
0
 
0
   def insert(range, marker)
0
@@ -103,7 +102,7 @@ class IntervalSkipList
0
 
0
   protected
0
   attr_reader :head, :ranges
0
-  
0
+
0
   def insert_node(key)
0
     path = make_path
0
     found_node = find(key, path)
0
@@ -112,6 +111,22 @@ class IntervalSkipList
0
     else
0
       return Node.new(key, next_node_height, path)
0
     end
0
+  end  
0
+
0
+  def containing_with_node(n)
0
+    containing = []
0
+    cur_node = head
0
+    (max_height - 1).downto(0) do |cur_level|
0
+      while (next_node = cur_node.forward[cur_level]) && next_node.key <= n
0
+        cur_node = next_node
0
+        if cur_node.key == n
0
+          return containing + (cur_node.markers - cur_node.endpoint_of), cur_node
0
+        end
0
+      end
0
+      containing.concat(cur_node.forward_markers[cur_level])
0
+    end
0
+
0
+    return containing, cur_node
0
   end
0
 
0
   def delete_node(key)

0
@@ -12,6 +12,10 @@ class IntervalSkipList
0
       promote_markers(path)
0
     end
0
 
0
+    def all_forward_markers
0
+      markers.flatten
0
+    end
0
+
0
     def delete(path)
0
       0.upto(top_level) do |i|
0
         path[i].forward[i] = forward[i]