diff --git a/src/slam_wrapper.cpp b/src/slam_wrapper.cpp
index 47464f8..7da65b4 100644
--- a/src/slam_wrapper.cpp
+++ b/src/slam_wrapper.cpp
@@ -23,26 +23,24 @@
 }
 
 void SlamWrapper::qt_notice_handler(const void *message) {
-    int index_, begin_, end_, feedback_, arrive_;
-    auto seq = static_cast<const String_ *>(message);
-    std::string str_, notice_;
+    const auto seq = static_cast<const String_ *>(message);
+    std::string str_;
 
-    begin_ = seq->data().find("index:", 0); // Instruction unique identifier
-    end_ = seq->data().find(";", begin_);
+    int begin_ = seq->data().find("index:", 0); // Instruction unique identifier
+    int end_ = seq->data().find(";", begin_);
     str_ = seq->data().substr(begin_ + 6, end_ - begin_ - 6);
-    index_ = atoi(str_.c_str());
+    const int index_ = atoi(str_.c_str());
 
     begin_ = seq->data().find("notice:", 0); // Prompt message
     end_ = seq->data().find(";", begin_);
-    notice_ = seq->data().substr(begin_ + 7, end_ - begin_ - 7);
+    const std::string notice_ = seq->data().substr(begin_ + 7, end_ - begin_ - 7);
 
     if (index_ <= 10000) {
         // Command execution feedback
         begin_ = seq->data().find("feedback:", 0);
         end_ = seq->data().find(";", begin_);
         str_ = seq->data().substr(begin_ + 9, end_ - begin_ - 9);
-        feedback_ = atoi(str_.c_str());
-        if (feedback_ == 0 || feedback_ == -1)
+        if (const int feedback_ = atoi(str_.c_str()); feedback_ == 0 || feedback_ == -1)
             std::cout << "\033[1;31m"
                     << "Command execution failed with index = " << index_ << "."
                     << "\033[0m";
@@ -52,7 +50,7 @@
         begin_ = seq->data().find("arrive:", 0);
         end_ = seq->data().find(";", begin_);
         str_ = seq->data().substr(begin_ + 7, end_ - begin_ - 7);
-        arrive_ = atoi(str_.c_str());
+        const int arrive_ = atoi(str_.c_str());
         std::cout << " I arrived node " << arrive_ << ". " << notice_ << std::endl;
         if (arrive_ == 1) {
             //发送暂停指令