diff --git a/a8/commonrank.h b/a8/commonrank.h
index 67e671b..1810208 100644
--- a/a8/commonrank.h
+++ b/a8/commonrank.h
@@ -64,6 +64,20 @@ namespace a8
             return set_.find(val) != set_.end();
         }
 
+        void Remove(T* val)
+        {
+            if (!Exists(val)) {
+                return;
+            }
+            {
+                auto itr = std::find(list_.begin(), list_.end(), val);
+                if (itr != list_.end()) {
+                    list_.erase(itr);
+                }
+            }
+            set_.erase(val);
+        }
+
     };
 
     template <typename T>