diff --git a/utils/trie/trie.hpp b/utils/trie/trie.hpp
index 28c075e..6d11ecb 100644
--- a/utils/trie/trie.hpp
+++ b/utils/trie/trie.hpp
@@ -152,7 +152,7 @@
                                              // container
     , children_(bucket_traits(buckets_.get(), bucketSize_))
     , payload_(PayloadTraits::empty_payload)
-    , parent_(0)
+    , parent_(nullptr)
   {
   }