diff --git a/include/concise.h b/include/concise.h
index 3668a93..bc5b174 100644
--- a/include/concise.h
+++ b/include/concise.h
@@ -433,7 +433,7 @@ template <bool wah_mode = false> class ConciseSet {
         return 0;
       }
       if (other.isEmpty()) {
-        return this->count();
+        return this->size();
       }
       size_t answer = 0;
       // scan "this" and "other"