removed unused include
diff --git a/kll/include/kll_quantile_calculator_impl.hpp b/kll/include/kll_quantile_calculator_impl.hpp
index 77aeb05..cb92674 100644
--- a/kll/include/kll_quantile_calculator_impl.hpp
+++ b/kll/include/kll_quantile_calculator_impl.hpp
@@ -24,8 +24,6 @@
 #include <cmath>
 #include <algorithm>
 
-#include <iostream>
-
 #include "kll_helper.hpp"
 
 namespace datasketches {