1 files changed, 9 insertions, 0 deletions
diff --git a/dtrain/score.h b/dtrain/score.h
index e9130e18..4314157b 100644
--- a/dtrain/score.h
+++ b/dtrain/score.h
@@ -29,6 +29,7 @@ struct ScorePair
   double GetScore() { return score_; }
 };
 
+
 typedef vector<ScorePair> Scores;
 
 
@@ -55,6 +56,14 @@ struct NgramCounts
     }
   }
 
+  const NgramCounts
+  operator+( const NgramCounts &other ) const
+  {
+    NgramCounts result = *this;
+    result += other;
+    return result;
+  }
+
   void
   add( size_t count, size_t ref_count, size_t i )
   {