diff --git a/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/cal.cpp b/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/cal.cpp
index 715846b..eb071d3 100644
--- a/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/cal.cpp
+++ b/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/cal.cpp
@@ -59,9 +59,6 @@ QString inToPost(QString infix) {
     case '.':
       postfix.push_back(current);
       break;
-    case '%':
-      postfix.push_back(current);
-      break;
     case '(':
       stack.push(current); //左括号直接入栈
       break;
diff --git a/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.cpp b/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.cpp
index ec7ffe9..e496324 100644
--- a/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.cpp
+++ b/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.cpp
@@ -2,10 +2,11 @@
 #include "cal.h"
 #include "ui_mainwindow.h"
 #include <QClipboard>
+#include <QDebug>
 #include <QMessageBox>
 #include <QScrollBar>
 static QString displayText;
-
+static QString calcLog;
 MainWindow::MainWindow(QWidget *parent)
     : QMainWindow(parent), ui(new Ui::MainWindow) {
   ui->setupUi(this);
@@ -52,13 +53,19 @@ void MainWindow::on_equalBtn_clicked() {
   if (isFinished)
     return;
   try {
-    result = compute(inToPost(ui->lineEdit->toPlainText().right(
+    QString s = inToPost(ui->lineEdit->toPlainText().right(
         ui->lineEdit->toPlainText().size() -
-        (ui->lineEdit->toPlainText().lastIndexOf("\n") + 1))));
+        (ui->lineEdit->toPlainText().lastIndexOf("\n") + 1)));
+    std::cout << s.toStdString() << std::endl;
+    result = compute(s);
 
   } catch (...) {
     abortOperation();
   }
+  calcLog += ui->lineEdit->toPlainText().right(
+                 ui->lineEdit->toPlainText().size() -
+                 (ui->lineEdit->toPlainText().lastIndexOf("\n") + 1)) +
+             '=' + QString::number(result) + '\n';
   displayText += '=' + QString::number(result);
   ui->lineEdit->setPlainText(displayText);
   ui->lineEdit->verticalScrollBar()->setValue(
@@ -75,7 +82,7 @@ void MainWindow::connectSlots() {
       ui->digitBtn8, ui->digitBtn9,   ui->addBtn,    ui->subtractionBtn,
       ui->mulBtn,    ui->divisionBtn, ui->squareBtn, ui->pointBtn,
       ui->LBtn,      ui->RBtn,        ui->cBtn,      ui->sBtn,
-      ui->perBtn};
+      ui->sciBtn};
   for (auto btn : digitBtns)
     connect(btn, &QPushButton::clicked, this, &MainWindow::normalClicked);
 }
@@ -94,6 +101,12 @@ void MainWindow::on_actionClearHistroy_triggered() {
       ui->lineEdit->verticalScrollBar()->maximum());
 }
 
+void MainWindow::on_actionShow_History_H_triggered() {
+  ui->lineEdit->setPlainText(calcLog);
+  ui->lineEdit->verticalScrollBar()->setValue(
+      ui->lineEdit->verticalScrollBar()->maximum());
+}
+
 void MainWindow::on_clearLine_clicked() {
   isFinished = false;
   displayText.chop(displayText.size() - displayText.lastIndexOf('\n') - 1);
@@ -165,15 +178,21 @@ void MainWindow::keyPressEvent(QKeyEvent *event) {
   case Qt::Key_AsciiCircum:
     emit ui->squareBtn->clicked();
     break;
-  case Qt::Key_BracketLeft:
+  case Qt::Key_ParenLeft:
     emit ui->LBtn->clicked();
     break;
-  case Qt::Key_BracketRight:
+  case Qt::Key_ParenRight:
     emit ui->RBtn->clicked();
     break;
   case Qt::Key_A:
     emit ui->ansBtn->clicked();
     break;
+  case Qt::Key_S:
+    emit ui->sBtn->clicked();
+    break;
+  case Qt::Key_C:
+    emit ui->cBtn->clicked();
+    break;
   case Qt::Key_Equal:
   case Qt::Key_Enter:
     emit ui->equalBtn->clicked();
@@ -190,3 +209,25 @@ void MainWindow::keyPressEvent(QKeyEvent *event) {
     break;
   }
 }
+
+void MainWindow::on_actionc_triggered() {
+  if (isFinished) {
+    isFinished = false;
+    displayText += '\n';
+  }
+  displayText += "299792458";
+  ui->lineEdit->setPlainText(displayText);
+  ui->lineEdit->verticalScrollBar()->setValue(
+      ui->lineEdit->verticalScrollBar()->maximum());
+}
+
+void MainWindow::on_actionpi_triggered() {
+  if (isFinished) {
+    isFinished = false;
+    displayText += '\n';
+  }
+  displayText += "3.1415926535";
+  ui->lineEdit->setPlainText(displayText);
+  ui->lineEdit->verticalScrollBar()->setValue(
+      ui->lineEdit->verticalScrollBar()->maximum());
+}
diff --git a/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.h b/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.h
index b019e0f..f802715 100644
--- a/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.h
+++ b/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.h
@@ -39,5 +39,8 @@ private slots:
 
   void keyPressEvent(QKeyEvent *event);
   void on_ansBtn_clicked();
+  void on_actionc_triggered();
+  void on_actionpi_triggered();
+  void on_actionShow_History_H_triggered();
 };
 #endif // MAINWINDOW_H
diff --git a/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.ui b/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.ui
index 3721112..3b77949 100644
--- a/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.ui
+++ b/SoftwareDesign/Lab4/Lab4-1_Calculator4490_v6/mainwindow.ui
@@ -6,12 +6,12 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>406</width>
-    <height>439</height>
+    <width>414</width>
+    <height>479</height>
    </rect>
   </property>
   <property name="windowTitle">
-   <string>Calculator_v3_4490</string>
+   <string>Calculator_v6_4490</string>
   </property>
   <property name="toolButtonStyle">
    <enum>Qt::ToolButtonTextOnly</enum>
@@ -168,13 +168,6 @@
       </property>
      </widget>
     </item>
-    <item row="8" column="0">
-     <widget class="QPushButton" name="perBtn">
-      <property name="text">
-       <string>%</string>
-      </property>
-     </widget>
-    </item>
     <item row="7" column="3">
      <widget class="QPushButton" name="cBtn">
       <property name="text">
@@ -189,6 +182,13 @@
       </property>
      </widget>
     </item>
+    <item row="8" column="2" colspan="2">
+     <widget class="QPushButton" name="equalBtn">
+      <property name="text">
+       <string>=</string>
+      </property>
+     </widget>
+    </item>
     <item row="8" column="1">
      <widget class="QPushButton" name="ansBtn">
       <property name="text">
@@ -196,10 +196,10 @@
       </property>
      </widget>
     </item>
-    <item row="8" column="2" colspan="2">
-     <widget class="QPushButton" name="equalBtn">
+    <item row="8" column="0">
+     <widget class="QPushButton" name="sciBtn">
       <property name="text">
-       <string>=</string>
+       <string>*10^</string>
       </property>
      </widget>
     </item>
@@ -210,7 +210,7 @@
     <rect>
      <x>0</x>
      <y>0</y>
-     <width>406</width>
+     <width>414</width>
      <height>30</height>
     </rect>
    </property>
@@ -220,8 +220,17 @@
     </property>
     <addaction name="actionPaste"/>
     <addaction name="actionClearHistroy"/>
+    <addaction name="actionShow_History_H"/>
+   </widget>
+   <widget class="QMenu" name="menuConstant">
+    <property name="title">
+     <string>Constant</string>
+    </property>
+    <addaction name="actionc"/>
+    <addaction name="actionpi"/>
    </widget>
    <addaction name="menuMenu"/>
+   <addaction name="menuConstant"/>
   </widget>
   <widget class="QStatusBar" name="statusbar"/>
   <action name="actionPaste">
@@ -234,12 +243,30 @@
   </action>
   <action name="actionClearHistroy">
    <property name="text">
-    <string>Clear Histroy(U)</string>
+    <string>Clear Buffer(U)</string>
    </property>
    <property name="shortcut">
     <string>Ctrl+U</string>
    </property>
   </action>
+  <action name="actionc">
+   <property name="text">
+    <string>c</string>
+   </property>
+  </action>
+  <action name="actionpi">
+   <property name="text">
+    <string>pi</string>
+   </property>
+  </action>
+  <action name="actionShow_History_H">
+   <property name="text">
+    <string>Show History(H)</string>
+   </property>
+   <property name="shortcut">
+    <string>Ctrl+H</string>
+   </property>
+  </action>
  </widget>
  <resources/>
  <connections/>