基于Java编写简易的算式测试程序

import java.util.*;

public class Calculate {
    public static void main(String[] args) {
        //接受用户输入
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入题目的数量：");
        int n = sc.nextInt();

        //result保存算式答案，right保存答对题数，accuracy保存准确率
        int result = 0, right = 0;
        double accuracy;

        //开始计时
        long startTime = System.currentTimeMillis();

        //打印加减乘三种算式
        Random r = new Random();
        for (int i = 0; i < n; i++) {
            int i1 = r.nextInt(50);
            int i2 = r.nextInt(50);
            int i3 = r.nextInt(3);

            //判断进行哪种运算
            if (i3 == 0) {
                System.out.println(i1 + "-" + i2 + "=");
                result = i1 - i2;
            } else if (i3 == 1) {
                System.out.println(i1 + "+" + i2 + "=");
                result = i1 + i2;
            } else {
                System.out.println(i1 + "*" + i2 + "=");
                result = i1 * i2;
            }

            //输出正确与否信息，同时判断是否增加答对题数
            int a = sc.nextInt();
            if (a == result) {
                System.out.println("答对了！");
                right += 1;
            } else {
                System.out.println("答错了，继续加油！");
            }
        }

        //计算准确率
        accuracy = (right * 1.0 / n) * 100;

        //结束计时
        long endTime = System.currentTimeMillis();

        //输出成绩
        System.out.print("恭喜你，一共答对了" + right + "题" + "," + "正确率:" + accuracy + "%" + "," + "用时：" + (endTime - startTime) / 1000 + "秒");

        //关闭资源的使用，可不加
        sc.close();
    }
}