diff --git a/.settings/org.eclipse.core.resources.prefs b/.settings/org.eclipse.core.resources.prefs
new file mode 100644
index 0000000000000000000000000000000000000000..0b5440269e1ddf9ceed9a17e7a6ee9bf8bae27a8
--- /dev/null
+++ b/.settings/org.eclipse.core.resources.prefs
@@ -0,0 +1,2 @@
+eclipse.preferences.version=1
+encoding//src/start/Calculator.java=UTF-8
diff --git a/src/start/Calculator.java b/src/start/Calculator.java
new file mode 100644
index 0000000000000000000000000000000000000000..11327db5bee4429607082437c906131960bfe1ae
--- /dev/null
+++ b/src/start/Calculator.java
@@ -0,0 +1,174 @@
+package start;
+
+import javax.swing.*;
+import java.awt.*;
+import javax.swing.border.*;
+import java.awt.event.*;
+import java.lang.*;
+
+public class Calculator extends JFrame implements ActionListener {
+	/************ 北部控件 *************/
+	JPanel northP = new JPanel();
+	JTextField inputtext = new JTextField();
+
+	/************ 中间控件 *************/
+	JPanel centerP = new JPanel();
+
+	public Calculator() throws HeadlessException {
+		this.init();
+		this.addNorthComponent();
+		this.addCenterComponent();
+
+	}
+
+	public void init() {
+		this.setTitle("Calculator");
+		this.setSize(490, 530);
+		this.setResizable(false);// 设置窗体不可调整大小
+		this.setLocationRelativeTo(null);// 设置窗体初始位置居中
+		this.setLayout(new BorderLayout());
+		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+	}
+
+	public void addNorthComponent() {
+		inputtext.setPreferredSize(new Dimension(470, 60));
+		inputtext.setFont(new Font("Calibre", Font.PLAIN, 45));
+		inputtext.setBackground(new Color(32,32,33));
+		inputtext.setForeground(new Color(255, 255, 255));
+		northP.setBackground(new Color(32,32,33));
+		LineBorder border = new LineBorder(Color.LIGHT_GRAY, 2, true);
+		inputtext.setBorder(border);
+		northP.add(inputtext);
+
+		this.add(northP, BorderLayout.NORTH);// 把C控件放到Calculator窗体北面
+
+	}
+
+	public void addCenterComponent() {
+		centerP.setBackground(new Color(32,32,33));
+		JButton btn[][] = new JButton[6][4];
+		String[][] btn_text = { { "%", "±", "C", "<-" }, { "1/x", "^2", "✓", "÷" }, { "7", "8", "9", "×" },
+				{ "4", "5", "6", "-" }, { "1", "2", "3", "+" }, { "00", "0", ".", "=" } };
+
+		this.centerP.setLayout(new GridLayout(6, 6));
+
+		for (int i = 0; i < 6; i++) {
+			for (int j = 0; j < 4; j++) {
+				btn[i][j] = new JButton(btn_text[i][j]);
+				btn[i][j].setBackground(new Color(70,70,70));
+				btn[i][j].setForeground(Color.white);
+				btn[i][j].setFont(new Font("", Font.BOLD, 30));
+				if (i < 2) {
+					btn[i][j].setBackground(new Color(52,49,49));
+				}
+				if (j > 2) {
+					btn[i][j].setBackground(new Color(52,49,49));
+				}
+
+				btn[i][j].addActionListener(this);
+				centerP.add(btn[i][j]);
+			}
+		}
+
+		this.add(centerP, BorderLayout.CENTER);
+	}
+
+	private String firstInput = null;
+	private String operator = null;
+
+	@Override
+	public void actionPerformed(ActionEvent e) {
+		// TODO 自动生成的方法存根
+		String clickStr = e.getActionCommand();
+		if (".0123456789".indexOf(clickStr) != -1) {//数字输入
+			this.inputtext.setText(inputtext.getText() + clickStr);
+			this.inputtext.setHorizontalAlignment(JTextField.RIGHT);
+
+		} 
+		else if(clickStr.equals("00")) {
+			this.inputtext.setText(inputtext.getText() + clickStr);
+			this.inputtext.setHorizontalAlignment(JTextField.RIGHT);
+		}
+		else if (clickStr.matches("[\\+\\-×÷±]{1}")) {
+			operator = clickStr;
+			firstInput = this.inputtext.getText();
+			this.inputtext.setText(null);
+		} 
+		else if (clickStr.equals("<-")) {//删除键
+			String str3 = inputtext.getText();
+			str3 = str3.substring(0, str3.length() - 1);
+			inputtext.setText(str3);
+		} 
+		else if (clickStr.equals("=")) {//等号键
+			Double a = Double.valueOf(firstInput);
+			Double b = Double.valueOf(this.inputtext.getText());
+			Double result = null;
+			switch (operator) {
+			case "+":
+				result = a + b;
+				break;
+			case "-":
+				result = a - b;
+				break;
+			case "×":
+				result = a * b;
+				break;
+			case "÷":
+				if(b !=0) {
+					result = a / b;
+				}
+				break;
+			case "±":
+				Double a1,a2;
+				a1 = a+b;
+				a2 = a-b;
+				this.inputtext.setText(a1.toString()+"&"+a2.toString());
+				break;
+			}
+			this.inputtext.setText(result.toString());
+		} 
+		else if (clickStr.equals("1/x")) {//倒数运算
+			String temp = inputtext.getText();
+			String str4;
+			double x = Double.valueOf(temp);
+			if(x != 0) {
+			x = 1/x;
+			str4 = String.valueOf(x);
+			this.inputtext.setText(str4);
+			}
+		} 
+		else if(clickStr.equals("^2")) {//平方运算
+			String temp = inputtext.getText();
+			String str5;
+			double x = Double.valueOf(temp);
+			x = x * x;
+			str5 = String.valueOf(x);
+			this.inputtext.setText(str5);
+		}
+		else if(clickStr.equals("✓")) {//开方运算
+			String temp = inputtext.getText();
+			String str6;
+			double x = Double.valueOf(temp);
+			x = Math.sqrt(x);
+			str6 = String.valueOf(x);
+			this.inputtext.setText(str6);
+		}
+		else if(clickStr.equals("%")) {
+			String temp = inputtext.getText();
+			String str7;
+			double x = Double.valueOf(temp);
+			x = x / 100;
+			str7 = String.valueOf(x);
+			this.inputtext.setText(str7);
+		}
+		else if (clickStr.equals("C")) {//清空
+			inputtext.setText("");
+		}
+	}
+
+	public static void main(String[] args) {
+		// TODO 自动生成的方法存根
+		Calculator Calculator = new Calculator();
+		Calculator.setVisible(true);
+	}
+}