diff --git a/src/DictTrie.hpp b/src/DictTrie.hpp
index 4fdd478..bed15cf 100644
--- a/src/DictTrie.hpp
+++ b/src/DictTrie.hpp
@@ -66,12 +66,12 @@ class DictTrie {
   const DictUnit* find(Unicode::const_iterator begin, Unicode::const_iterator end) const {
     return trie_->find(begin, end);
   }
-  bool find(Unicode::const_iterator begin, Unicode::const_iterator end, DagType& dag, size_t offset = 0) const {
-    return trie_->find(begin, end, dag, offset);
+  bool find(Unicode::const_iterator begin, Unicode::const_iterator end, LocalVector<pair<size_t, const DictUnit*> >& nexts, size_t offset = 0) const {
+    return trie_->find(begin, end, nexts, offset);
   }
   void find(Unicode::const_iterator begin,
     Unicode::const_iterator end,
-    vector<SegmentChar>& res) const {
+    vector<Dag>& res) const {
     trie_->find(begin, end, res);
   }
   bool isUserDictSingleChineseWord(const Unicode::value_type& word) const {
@@ -79,7 +79,7 @@ class DictTrie {
   }
   double getMinWeight() const {
     return minWeight_;
-  };
+  }
 
  private:
   void createTrie_(const vector<DictUnit>& dictUnits) {
diff --git a/src/FullSegment.hpp b/src/FullSegment.hpp
index 55594be..6c8153f 100644
--- a/src/FullSegment.hpp
+++ b/src/FullSegment.hpp
@@ -31,7 +31,7 @@ class FullSegment: public SegmentBase {
   bool cut(Unicode::const_iterator begin, Unicode::const_iterator end, 
         vector<Unicode>& res) const {
     //resut of searching in trie tree
-    DagType tRes;
+    LocalVector<pair<size_t, const DictUnit*> > tRes;
 
     //max index of res's words
     int maxIdx = 0;
@@ -45,9 +45,7 @@ class FullSegment: public SegmentBase {
     for (Unicode::const_iterator uItr = begin; uItr != end; uItr++) {
       //find word start from uItr
       if (dictTrie_->find(uItr, end, tRes, 0)) {
-        for(DagType::const_iterator itr = tRes.begin(); itr != tRes.end(); itr++)
-          //for (vector<pair<size_t, const DictUnit*> >::const_iterator itr = tRes.begin(); itr != tRes.end(); itr++)
-        {
+        for(LocalVector<pair<size_t, const DictUnit*> >::const_iterator itr = tRes.begin(); itr != tRes.end(); itr++) {
           wordLen = itr->second->word.size();
           if (wordLen >= 2 || (tRes.size() == 1 && maxIdx <= uIdx)) {
             res.push_back(itr->second->word);
diff --git a/src/MPSegment.hpp b/src/MPSegment.hpp
index 0e30baf..1d9cd16 100644
--- a/src/MPSegment.hpp
+++ b/src/MPSegment.hpp
@@ -48,7 +48,7 @@ class MPSegment: public SegmentBase {
   }
 
   bool cut(Unicode::const_iterator begin , Unicode::const_iterator end, vector<Unicode>& res) const {
-    vector<SegmentChar> segmentChars;
+    vector<Dag> segmentChars;
 
     dictTrie_->find(begin, end, segmentChars);
 
@@ -63,16 +63,16 @@ class MPSegment: public SegmentBase {
   }
 
  private:
-  void calcDP_(vector<SegmentChar>& segmentChars) const {
+  void calcDP_(vector<Dag>& segmentChars) const {
     size_t nextPos;
     const DictUnit* p;
     double val;
 
-    for(vector<SegmentChar>::reverse_iterator rit = segmentChars.rbegin(); rit != segmentChars.rend(); rit++) {
+    for(vector<Dag>::reverse_iterator rit = segmentChars.rbegin(); rit != segmentChars.rend(); rit++) {
       rit->pInfo = NULL;
       rit->weight = MIN_DOUBLE;
-      assert(!rit->dag.empty());
-      for(DagType::const_iterator it = rit->dag.begin(); it != rit->dag.end(); it++) {
+      assert(!rit->nexts.empty());
+      for(LocalVector<pair<size_t, const DictUnit*> >::const_iterator it = rit->nexts.begin(); it != rit->nexts.end(); it++) {
         nextPos = it->first;
         p = it->second;
         val = 0.0;
@@ -92,7 +92,7 @@ class MPSegment: public SegmentBase {
       }
     }
   }
-  void cut_(const vector<SegmentChar>& segmentChars, 
+  void cut_(const vector<Dag>& segmentChars, 
         vector<Unicode>& res) const {
     size_t i = 0;
     while(i < segmentChars.size()) {
diff --git a/src/QuerySegment.hpp b/src/QuerySegment.hpp
index 617d4f2..bd8e676 100644
--- a/src/QuerySegment.hpp
+++ b/src/QuerySegment.hpp
@@ -56,7 +56,6 @@ class QuerySegment: public SegmentBase {
     return true;
   }
 
-
   bool cut(Unicode::const_iterator begin, Unicode::const_iterator end, vector<string>& res) const {
     vector<Unicode> uRes;
     if (!cut(begin, end, uRes)) {
diff --git a/src/Trie.hpp b/src/Trie.hpp
index 3afda9b..18e1b82 100644
--- a/src/Trie.hpp
+++ b/src/Trie.hpp
@@ -21,16 +21,14 @@ inline ostream & operator << (ostream& os, const DictUnit& unit) {
   return os << string_format("%s %s %.3lf", s.c_str(), unit.tag.c_str(), unit.weight);
 }
 
-typedef LocalVector<std::pair<size_t, const DictUnit*> > DagType;
-
-struct SegmentChar {
+struct Dag {
   uint16_t uniCh;
-  DagType dag;
+  LocalVector<pair<size_t, const DictUnit*> > nexts;
   const DictUnit * pInfo;
   double weight;
   size_t nextPos;
-  SegmentChar() : uniCh(), pInfo(NULL), weight(0.0), nextPos(0) {}
-  ~SegmentChar() {}
+  Dag():uniCh(0), pInfo(NULL), weight(0.0), nextPos(0) {
+  }
 };
 
 typedef Unicode::value_type TrieKey;
@@ -47,10 +45,23 @@ class TrieNode {
 class Trie {
  public:
   static const size_t BASE_SIZE = (1 << (8 * (sizeof(TrieKey))));
- public:
   Trie(const vector<Unicode>& keys, const vector<const DictUnit*>& valuePointers) {
     _createTrie(keys, valuePointers);
   }
+  ~Trie() {
+    for (size_t i = 0; i < BASE_SIZE; i++) {
+      if (_base[i].next == NULL) {
+        continue;
+      }
+      for (TrieNode::NextMap::iterator it = _base[i].next->begin(); it != _base[i].next->end(); it++) {
+        _deleteNode(it->second);
+        it->second = NULL;
+      }
+      delete _base[i].next;
+      _base[i].next = NULL;
+    }
+  }
+
   const DictUnit* find(Unicode::const_iterator begin, Unicode::const_iterator end) const {
     if (begin == end) {
       return NULL;
@@ -71,11 +82,9 @@ class Trie {
     return ptNode->ptValue;
   }
 
-  void find(
-    Unicode::const_iterator begin,
+  void find(Unicode::const_iterator begin,
     Unicode::const_iterator end,
-    vector<struct SegmentChar>& res
-  ) const {
+    vector<struct Dag>& res) const {
     res.resize(end - begin);
 
     const TrieNode *ptNode = NULL;
@@ -106,7 +115,7 @@ class Trie {
   bool find(
     Unicode::const_iterator begin,
     Unicode::const_iterator end,
-    DagType & res,
+    LocalVector<pair<size_t, const DictUnit*> > & res,
     size_t offset = 0) const {
     if (begin == end) {
       return !res.empty();
@@ -135,20 +144,6 @@ class Trie {
     }
     return !res.empty();
   }
-  ~Trie() {
-    for (size_t i = 0; i < BASE_SIZE; i++) {
-      if (_base[i].next == NULL) {
-        continue;
-      }
-      for (TrieNode::NextMap::iterator it = _base[i].next->begin(); it != _base[i].next->end(); it++) {
-        _deleteNode(it->second);
-        it->second = NULL;
-      }
-      delete _base[i].next;
-      _base[i].next = NULL;
-    }
-  }
-
   void insertNode(const Unicode& key, const DictUnit* ptValue) {
     if (key.begin() == key.end()) {
       return;
diff --git a/test/unittest/TTrie.cpp b/test/unittest/TTrie.cpp
index cf18fd3..628a931 100644
--- a/test/unittest/TTrie.cpp
+++ b/test/unittest/TTrie.cpp
@@ -32,9 +32,7 @@ TEST(DictTrieTest, Test1) {
 
   EXPECT_EQ("[\"26469\", \"21040\"] v -8.870", s2);
   word = "清华大学";
-  LocalVector<pair<size_t, const DictUnit*> > res;
-  //vector<pair<size_t, const DictUnit* > resMap;
-  LocalVector<pair<size_t, const DictUnit*> > res2;
+  LocalVector<pair<size_t, const DictUnit*> > res, res2;
   const char * words[] = {"清", "清华", "清华大学"};
   for(size_t i = 0; i < sizeof(words)/sizeof(words[0]); i++) {
     ASSERT_TRUE(TransCode::decode(words[i], uni));
@@ -70,6 +68,6 @@ TEST(DictTrieTest, automation) {
   string word = "abcderf";
   Unicode unicode;
   ASSERT_TRUE(TransCode::decode(word, unicode));
-  vector<struct SegmentChar> res;
+  vector<struct Dag> res;
   trie.find(unicode.begin(), unicode.end(), res);
 }