diff --git a/y2020/constants.cc b/y2020/constants.cc
index 07d10ee..893613a 100644
--- a/y2020/constants.cc
+++ b/y2020/constants.cc
@@ -1,7 +1,6 @@
 #include "y2020/constants.h"
 
-#include <inttypes.h>
-
+#include <cinttypes>
 #include <map>
 
 #if __has_feature(address_sanitizer)