//package Test8;

import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
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using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;

namespace Calculator
{
    static class Program
    {
        /// <summary>
        /// 应用程序的主入口点。
        /// </summary>
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