diff --git a/paddle/fluid/operators/hierarchical_sigmoid_op.h b/paddle/fluid/operators/hierarchical_sigmoid_op.h
index 35a1de3e1917f704727ac6e65b02d37e5bbc94c4..418fe86f69fff392f103f53a98cd5d59038ee7bf 100644
--- a/paddle/fluid/operators/hierarchical_sigmoid_op.h
+++ b/paddle/fluid/operators/hierarchical_sigmoid_op.h
@@ -43,9 +43,7 @@ std::vector<int64_t> cal_rows(const framework::LoDTensor* path) {
       }
     }
   }
-  for (std::set<int64_t>::iterator it = tmp.begin(); it != tmp.end(); ++it) {
-    rows.push_back(*it);
-  }
+  rows.assign(tmp.begin(), tmp.end());
   return rows;
 }