diff --git a/Readme.markdown b/Readme.markdown
index 13d7825..0c7698a 100644
--- a/Readme.markdown
+++ b/Readme.markdown
@@ -77,6 +77,7 @@ Python language:
 
 C++ language:
 
+    #include <string>
     #include <vector>
     #include "QrCode.hpp"
     using namespace qrcodegen;