diff --git a/.gitignore b/.gitignore
index 559534d..f047bef 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,4 +6,4 @@ tags
 *.ut
 log
 main
-cmlib.a
+lib*.a
diff --git a/demo/segment_demo.cpp b/demo/segment_demo.cpp
index 6312dbe..422e6d5 100644
--- a/demo/segment_demo.cpp
+++ b/demo/segment_demo.cpp
@@ -9,8 +9,8 @@ int main(int argc, char ** argv)
 {
 	if(argc < 2)
 	{
-		cerr<<"usage: "<<argv[0]<<" filename"<<endl;
-		return 1;
+		cout<<"usage: "<<argv[0]<<" <filename>"<<endl;
+		return -1;
 	}
 	Segment seg;
 	if(!seg.init())
diff --git a/src/Trie.cpp b/src/Trie.cpp
index 71251e5..66215b2 100644
--- a/src/Trie.cpp
+++ b/src/Trie.cpp
@@ -77,10 +77,10 @@ namespace CppJieba
 			return false;
 		}
 		bool res = false;
-		res = _buildTree(filePath);
+		res = _trieInsert(filePath);
 		if(!res)
 		{
-			LogError("_buildTree failed.");
+			LogError("_trieInsert failed.");
 			return false;
 		}
 		res = _countWeight();
@@ -92,40 +92,35 @@ namespace CppJieba
 		return true;
 	}
 
-    bool Trie::_buildTree(const char * const filePath)
+    bool Trie::_trieInsert(const char * const filePath)
     {
 		
         ifstream ifile(filePath);
         string line;
         vector<string> vecBuf;
+		
+		TrieNodeInfo nodeInfo;
         while(getline(ifile, line))
         {
             vecBuf.clear();
             splitStr(line, vecBuf, " ");
-            if(3 != vecBuf.size())
+            if(3 < vecBuf.size())
             {
                 LogError(string_format("line[%s] illegal.", line.c_str()));
                 return false;
             }
-            string chWord = vecBuf[0];
-            uint count = atoi(vecBuf[1].c_str());
-            const string& tag = vecBuf[2];
+			nodeInfo.word = vecBuf[0];
+			nodeInfo.count = atoi(vecBuf[1].c_str());
+			if(3 == vecBuf.size())
+			{
+				nodeInfo.tag = vecBuf[2];
+			}
 
 			//insert node
-			TrieNodeInfo nodeInfo;
-			nodeInfo.word = chWord;
-			nodeInfo.wLen = 0;
-			nodeInfo.count = count;
-			nodeInfo.tag = tag;
-
-			bool flag = insert(nodeInfo);
-			if(!flag)
+			if(!insert(nodeInfo))
 			{
 				LogError("insert node failed!");
-				return false;
 			}
-			
-
         }
         return true;
     }
diff --git a/src/Trie.h b/src/Trie.h
index 39e3a91..574adfa 100644
--- a/src/Trie.h
+++ b/src/Trie.h
@@ -35,10 +35,8 @@ namespace CppJieba
 		double weight;
 		TrieNodeInfo()
 		{
-			word = "";
 			wLen = 0;
 			count = 0;
-			tag = "";
 			weight = 0.0;
 		}
 	};
@@ -101,7 +99,7 @@ namespace CppJieba
 			bool insert(const TrieNodeInfo& nodeInfo);
 
         private:
-			bool _buildTree(const char * const filePath);
+			bool _trieInsert(const char * const filePath);
 			bool _countWeight();
             bool _deleteNode(TrieNode* node);