iterator fix
diff --git a/req/include/req_sketch_impl.hpp b/req/include/req_sketch_impl.hpp
index 8b45bc9..ee6d9e1 100755
--- a/req/include/req_sketch_impl.hpp
+++ b/req/include/req_sketch_impl.hpp
@@ -766,9 +766,9 @@
template<typename T, typename C, typename S, typename A>
req_sketch<T, C, S, A>::const_iterator::const_iterator(LevelsIterator begin, LevelsIterator end):
-levels_it_(begin),
-levels_end_(end),
-compactor_it_((*levels_it_).begin())
+ levels_it_(begin),
+ levels_end_(end),
+ compactor_it_(begin == end ? nullptr : (*levels_it_).begin())
{}
template<typename T, typename C, typename S, typename A>
@@ -802,7 +802,7 @@
template<typename T, typename C, typename S, typename A>
std::pair<const T&, const uint64_t> req_sketch<T, C, S, A>::const_iterator::operator*() const {
- return std::pair<const T&, const uint64_t>(*compactor_it_, 1 << (*levels_it_).get_lg_weight());
+ return std::pair<const T&, const uint64_t>(*compactor_it_, 1ULL << (*levels_it_).get_lg_weight());
}
} /* namespace datasketches */
