add umt5 support

thirdparty/darts.h

@@ -4,6 +4,7 @@
 #include <cstdio>
 #include <exception>
 #include <new>
+#include <iostream>
 
 #define DARTS_VERSION "0.32"
 
@@ -1140,9 +1141,11 @@ inline void DawgBuilder::insert(const char *key, std::size_t length,
   if (value < 0) {
     DARTS_THROW("failed to insert key: negative value");
   } else if (length == 0) {
+    std::cout << value << std::endl;
     DARTS_THROW("failed to insert key: zero-length key");
   }
 
+
   id_type id = 0;
   std::size_t key_pos = 0;