diff --git a/grammar/main.cc b/grammar/main.cc
index 47b6152..3e4af82 100644
--- a/grammar/main.cc
+++ b/grammar/main.cc
@@ -5,11 +5,13 @@
 #include "CListener.h"
 #include "CParser.h"
 #include "CVisitor.h"
+#include <algorithm>
 #include <antlr4-runtime.h>
-#include <cstring>
 #include <llvm/Support/JSON.h>
 #include <llvm/Support/MemoryBuffer.h>
 #include <llvm/Support/raw_ostream.h>
+#include <string>
+#include <unordered_map>
 
 int main(int argc, char **argv) {
   auto llvmin = llvm::MemoryBuffer::getFileOrSTDIN("-");
@@ -18,44 +20,31 @@ int main(int argc, char **argv) {
   sysu_grammar::CLexer lexer(&input);
   antlr4::CommonTokenStream tokens(&lexer);
   tokens.fill();
-  if (argc >= 2 && !std::strcmp(argv[1], "-dump-tokens")) {
-// 请完成此处的词法分析器
-#if 0
+  if (argc >= 2 && argv[1] == std::string("-dump-tokens")) {
+    // 请完成此处的词法分析器
     for (auto token : tokens.getTokens()) {
-      llvm::outs() << token->toString() << "\n";
+      if (token->getChannel() != antlr4::Token::HIDDEN_CHANNEL) {
+        std::string t = lexer.getVocabulary().getSymbolicName(token->getType());
+        std::unordered_map<std::string, std::string> transform_table{
+            {"Int", "int"},
+            {"Identifier", "identifier"},
+            {"LeftParen", "l_paren"},
+            {"RightParen", "r_paren"},
+            {"LeftBrace", "l_brace"},
+            {"Return", "return"},
+            {"Constant", "numeric_constant"},
+            {"Semi", "semi"},
+            {"RightBrace", "r_brace"},
+            {"EOF", "eof"}};
+        if (transform_table.count(t))
+          t = transform_table[t];
+        llvm::outs() << t << " \'" << (t != "eof" ? token->getText() : "")
+                     << "\'\t\tLoc=<"
+                     << "<stdin>"
+                     << ":" << token->getLine() << ":"
+                     << token->getCharPositionInLine() + 1 << ">\n";
+      }
     }
-#else
-    llvm::outs()
-        << "int \'int\'               "
-           "Loc=<tester/functional/000_main.sysu.c:1:1> "
-        << "\n"
-        << "identifier \'main\'               "
-           "Loc=<tester/functional/000_main.sysu.c:1:5> "
-        << "\n"
-        << "l_paren \'(\'             "
-           "Loc=<tester/functional/000_main.sysu.c:1:9> "
-        << "\n"
-        << "r_paren \')\'             "
-           "Loc=<tester/functional/000_main.sysu.c:1:10> "
-        << "\n"
-        << "l_brace \'{\'             "
-           "Loc=<tester/functional/000_main.sysu.c:1:11> "
-        << "\n"
-        << "return \'return\'         "
-           "Loc=<tester/functional/000_main.sysu.c:2:5> "
-        << "\n"
-        << "numeric_constant \'3\'            "
-           "Loc=<tester/functional/000_main.sysu.c:2:12> "
-        << "\n"
-        << "semi \';\'                "
-           "Loc=<tester/functional/000_main.sysu.c:2:13> "
-        << "\n"
-        << "r_brace \'}\'             "
-           "Loc=<tester/functional/000_main.sysu.c:3:1> "
-        << "\n"
-        << "eof \'\'          Loc=<tester/functional/000_main.sysu.c:3:2> "
-        << "\n";
-#endif
     return 0;
   }
   sysu_grammar::CParser parser(&tokens);