用java随机生成10以内的四则混合运算题并存放到字符串组中

可以使用以下代码来随机生成10以内的四则混合运算题并存放到字符串数组中：

import java.util.Random;

public class Main {
    public static void main(String[] args) {
        Random random = new Random();
        String[] questions = new String[10];
        for (int i = 0; i < questions.length; i++) {
            int a = random.nextInt(10) + 1;
            int b = random.nextInt(10) + 1;
            int op = random.nextInt(4);
            String operator = "";
            int result = 0;
            switch (op) {
                case 0:
                    operator = "+";
                    result = a + b;
                    break;
                case 1:
                    operator = "-";
                    result = a - b;
                    break;
                case 2:
                    operator = "*";
                    result = a * b;
                    break;
                case 3:
                    operator = "/";
                    result = a / b;
                    break;
            }
            questions[i] = a + " " + operator + " " + b + " = ?";
        }
        for (String question : questions) {
            System.out.println(question);
        }
    }
}

运行结果类似于：

2 - 3 = ?
10 / 4 = ?
8 * 10 = ?
9 / 10 = ?
6 * 9 = ?
5 - 2 = ?
4 * 9 = ?
4 + 3 = ?
9 + 9 = ?
10 - 7 = ?