diff --git a/src/java2020spring/Cauculater.java b/src/java2020spring/Cauculater.java
new file mode 100644
index 0000000000000000000000000000000000000000..ab6a063b3e0aa99cf0e393a49368faced11c8d35
--- /dev/null
+++ b/src/java2020spring/Cauculater.java
@@ -0,0 +1,289 @@
+package java2020spring;
+
+
+import java.awt.*;
+import java.awt.event.*;
+import javax.swing.*;
+ 
+public class Cauculater extends JFrame  implements ActionListener{
+	private String[] KEY= { "7", "8", "9", "/", "sqrt", "4", "5", "6", "*", "%", "1", "2", "3", "-", "1/x", "0", "+/-", ".", "+", "="};
+	private String[] COM = {"Backspace", "CE", "C"};
+	private String[] M = {" ", "MC", "MR", "MS", "M+"};
+	private JButton key[] = new JButton[KEY.length];
+	private JButton com[] = new JButton[COM.length];
+	private JButton m[] = new JButton[M.length];
+	private JTextField resultText = new JTextField("0");
+	private boolean first = true;
+	private double resultNum = 0.0;
+    private String operator = "=";
+    private boolean operateFlag = true;
+    
+    private JTextField text1= new JTextField("");
+    private String storage = "";
+    private double n = 0.0;
+    
+    JMenuBar menubar;
+    
+    
+	public Cauculater() {
+		super();
+		init();
+        setTitle("计算器");
+        setLocation(100, 100);
+        pack();
+        menubar=new JMenuBar();
+		setJMenuBar(menubar); 
+		
+		JMenu mnNewMenu = new JMenu("编辑");
+		menubar.add(mnNewMenu);
+		JMenuItem card1=new JMenuItem("复制");
+		JMenuItem card2=new JMenuItem("粘贴");
+		mnNewMenu.add(card1);
+		mnNewMenu.add(card2);
+		
+		JMenu mnNewMenu_1 = new JMenu("查看");
+		menubar.add(mnNewMenu_1);
+		JMenuItem card3=new JMenuItem("科学型");
+		JMenuItem card4=new JMenuItem("标准型");
+		mnNewMenu_1.add(card3);
+		mnNewMenu_1.add(card4);
+		
+		JMenu mnNewMenu_2 = new JMenu("帮助");
+		menubar.add(mnNewMenu_2);
+		JMenuItem card5=new JMenuItem("关于");
+		mnNewMenu_2.add(card5);
+
+	}
+	
+	
+	public void init() {
+		resultText.setHorizontalAlignment(JTextField.RIGHT);
+		resultText.setEditable(false);
+		text1.setHorizontalAlignment(JTextField.LEFT);
+		text1.setEditable(false);
+		JPanel keyPanel = new JPanel();
+		keyPanel.setLayout(new GridLayout(4,5,5,5));
+		for(int i=0;i<key.length;i++) {
+			key[i] = new JButton(KEY[i]);
+			keyPanel.add(key[i]);
+			key[i].setForeground(Color.BLUE);
+			key[i].addActionListener(this);
+		}
+		key[3].setForeground(Color.red);
+        key[8].setForeground(Color.red);
+        key[13].setForeground(Color.red);
+        key[18].setForeground(Color.red);
+        key[19].setForeground(Color.red);
+        
+        JPanel comPanel = new JPanel();
+        comPanel.setLayout(new GridLayout(1, 3, 5, 5));
+        for (int i = 0; i < COM.length; i++) {
+            com[i] = new JButton(COM[i]);
+            comPanel.add(com[i]);
+            com[i].setForeground(Color.red);
+            com[i].addActionListener(this);
+        }
+        JPanel mPanel = new JPanel();
+        mPanel.setLayout(new GridLayout(5,1,5,5));
+        for(int i=0;i<M.length;i++) {
+        	m[i] = new JButton(M[i]);
+        	mPanel.add(m[i]);
+        	m[i].setForeground(Color.red);
+        	m[i].addActionListener(this);
+        }
+        
+        JPanel panel1 = new JPanel();
+        panel1.setLayout(new BorderLayout(5, 5));
+        panel1.add("North", comPanel);
+        panel1.add("Center", keyPanel);
+        JPanel top = new JPanel();
+        top.setLayout(new GridLayout(1, 2, 0, 0));
+        top.add(text1);
+        top.add(resultText);
+        getContentPane().setLayout(new BorderLayout(5, 5));
+        getContentPane().add("North", top);
+        getContentPane().add("Center", panel1);
+        getContentPane().add("West", mPanel);
+        }
+	
+	
+	public void actionPerformed(ActionEvent e) {
+		String label = e.getActionCommand();
+		if(label.equals(COM[0])) {
+			Backspace();
+	    } 
+		else if (label.equals(COM[1])) {
+			resultText.setText("0");
+	    }
+		else if (label.equals(COM[2])) {
+			C();
+		}
+		else if (label.equals(M[0])) {
+			resultText.setText("祝你快乐！");
+	    }
+        else if(label.equals(M[1])){
+			MC();
+		}
+        else if(label.equals(M[2])){
+			MR();
+		}
+        else if(label.equals(M[3])){
+			MS();
+		}
+        else if(label.equals(M[4])){
+			Madd();
+		}
+		else if ("0123456789.".indexOf(label) >= 0) {
+			Number(label);
+		}
+		
+		else {
+			Operator(label);
+		}
+		
+	}
+	
+	
+	private void MC() {
+		storage="";
+		text1.setText(null);
+	}
+
+
+	private void MR() {
+		
+		resultText.setText(storage);
+	}
+
+
+	private void MS() {
+		 storage = resultText.getText();
+		 text1.setText("M");
+	}
+
+
+	private void Madd() { 
+		n=Double.parseDouble(storage);
+		double x=Double.parseDouble(resultText.getText());
+		n=x+n;
+		String storage=""+n;
+		text1.setText("M");
+	}
+
+
+	private void Operator(String key) {
+		if(operator.equals("/")) {
+			if(getNumberFromText() == 0.0) {
+				operateFlag = false;
+                resultText.setText("除数不能为零");
+			}
+			else {
+				resultNum /= getNumberFromText();
+			}
+		}
+		else if (operator.equals("1/x")) {
+			if (resultNum == 0.0) {
+				operateFlag = false;
+                resultText.setText("零没有倒数");
+			}
+			else {
+				resultNum = 1 / resultNum;
+			}
+		}
+		else if (operator.equals("+")) {
+			resultNum += getNumberFromText();
+		}
+		else if (operator.equals("-")) {
+			resultNum -= getNumberFromText();
+		}
+		else if (operator.equals("*")) {
+			resultNum *= getNumberFromText();
+		}
+		else if (operator.equals("sqrt")) {
+			resultNum = Math.sqrt(resultNum);
+		}
+		else if (operator.equals("%")) {
+			resultNum = resultNum / 100;
+		}
+		else if (operator.equals("+/-")) {
+			resultNum = resultNum * (-1);
+		}
+		else if (operator.equals("=")) {
+			resultNum = getNumberFromText();
+		}
+		
+		if (operateFlag) {
+			long t1;
+            double t2;
+            t1 = (long) resultNum;
+            t2 = resultNum - t1;
+            if (t2 == 0) {
+            	 resultText.setText(String.valueOf(t1));
+            }
+            else {
+            	resultText.setText(String.valueOf(resultNum));
+            }
+		}
+		operator = key;
+        first = true;
+        operateFlag = true;
+		
+	}
+	
+	private void Number(String key) {
+		if(first) {
+			resultText.setText(key);
+		}
+		else if ((key.equals(".")) && (resultText.getText().indexOf(".") < 0)) {
+			resultText.setText(resultText.getText() + ".");  
+		}
+		else if (!key.equals(".")) {
+			resultText.setText(resultText.getText() + key);
+		}
+		first = false;
+	}
+	
+	
+	private void C() {
+		resultText.setText("0");
+        first = true;
+        operator = "=";
+		
+	}
+	
+	
+	private void Backspace() {
+		String text = resultText.getText();
+		int i =text.length();
+		if(i>0) {
+			text =text.substring(0,i-1);
+		}
+		if(i==0) {
+			resultText.setText("0");
+			first = true;
+			operator = "=";
+		}
+		else {
+			resultText.setText(text);
+		}
+	}
+	
+	
+	private double getNumberFromText() {
+		double result = 0;
+        try {
+            result = Double.valueOf(resultText.getText()).doubleValue();
+        } catch (NumberFormatException e) {
+        	
+        }
+		return result;
+	}
+	
+	
+    public static void main(String[] args) {
+		 Cauculater calculator = new Cauculater();
+	     calculator.setVisible(true);
+	     calculator.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+	    }
+ 
+}
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