package yunsuan;

import java.util.Scanner;

public class Yunsuan {

    public static void main(String[] args) {

        int a1,a2,a3;

        int b1,b2,b3;

        int m,n;

        int i=0;

        Scanner sc=new Scanner(System.in);

        String f[]=new String[4];

        f[0]="+";

        f[1]="-";

        f[2]="*";

        f[3]="/";

        System.out.println("请选择100以内或1000以内");

        m=sc.nextInt()+1;

        System.out.println("请输入要产生的题数");

        n=sc.nextInt();

        for(i=0;i<n;i++)

        {

        a1=(int)(Math.random()*m);

        a2=(int)(Math.random()*m);

        a3=(int)(Math.random()*m);

        //a4=(int)(Math.random()*m);

        b1=(int)(Math.random()*4);

        b2=(int)(Math.random()*4);

        //b3=(int)(Math.random()*4);

        System.out.println("第"+(i+1)+"题:"+a1+f[b1]+a2+f[b2]+a3+"=");

        }

        }

    }

package 登陆界面;

import java.awt.Color;

import java.awt.Container;

import java.awt.Dimension;

import java.awt.Toolkit;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.util.Random;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JLabel;

import javax.swing.JOptionPane;

import javax.swing.JPasswordField;

import javax.swing.JTextField;

public class Denglu {

    public static String creatZifu()

    {

        String str = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";

        Random random = new Random();

        StringBuffer sb = new StringBuffer();

        for (int i = 0; i < 4; i++)

        {

        int number = random.nextInt(str.length());

        sb.append(str.charAt(number));

        }

        return sb.toString();

    }

    public static void main(String[] args)

    {

        JFrame jFrame = new JFrame("登陆界面");

        //具体框架使用jFrame，文本框组件：JTextField；

        //密码框组件：JPasswordField；标签组件：JLabel；

        //复选框组件：JCheckBox；单选框组件：JRadioButton；按钮组件JButton。

        Dimension dimension = Toolkit.getDefaultToolkit().getScreenSize();

        jFrame.setBounds(((int)dimension.getWidth() - 200) / 2, ((int)dimension.getHeight() - 300) / 2, 400, 200);

        jFrame.setResizable(true);

        jFrame.setLayout(null);

        //添加标签，内容为“姓名”

        JLabel label1 = new JLabel("姓名:");

        label1.setBounds(10, 10, 100, 30);

        jFrame.add(label1);

        //添加标签，内容为“密码”

        JLabel label2 = new JLabel("密码:");

        label2.setBounds(10, 40, 100, 30);

        jFrame.add(label2);

        //添加标签，内容为“验证码”；

        JLabel label3 = new JLabel("验证码：");

        label3.setBounds(10, 70, 100, 30);

        jFrame.add(label3);

        //添加标签，并调用产生验证码的函数，并将其作为标签的内容

        JLabel label4 = new JLabel(creatZifu());

        String s;

        s=label4.getText();

        label4.setBounds(70, 70, 100, 30);

        label4.setForeground(Color.blue);

        jFrame.add(label4);

        //输入用户名；

        final JTextField text1 = new JTextField();

        text1.setBounds(50, 15, 130, 20);

        jFrame.add(text1);

        //输入密码；

        final JPasswordField text2 = new JPasswordField();

        text2.setBounds(50, 45, 130, 20);

        jFrame.add(text2);

        //输入验证码；

        final JTextField text3 = new JTextField();

        text3.setBounds(110, 75, 130, 20);

        jFrame.add(text3);

        JButton button1 = new JButton("取消");

        button1.setBounds(160, 105, 150, 30);

        button1.addActionListener(new ActionListener()

        {

                 public void actionPerformed(ActionEvent e)

                 {

                          jFrame.dispose();//关闭程序；

                 }

        });

        jFrame.add(button1);

        JButton button2 = new JButton("换一张?");

        button2.setBounds(250, 75, 100, 20);

        jFrame.add(button2);

        JButton button = new JButton("登录");

        button.setBounds(10, 105, 150, 30);

        jFrame.add(button);

        jFrame.setVisible(true);

}

}