java 要求程序运行随机生成两个两位数及加减号(要保证减法算式的被减数大于减数),显示题目让学生输入计算结果,程序判断结果是否正确。每次出十题,程序能给出统计结果(共答对几题答错几题)。

在Java中，你可以创建一个简单的控制台应用程序来完成这个任务。首先，你需要创建一个`QuestionGenerator`类用于生成题目，一个`Calculator`类用于处理用户输入并验证结果，以及一个`QuizManager`类来管理整个测试过程。这里是一个基础的示例：

import java.util.Random;
import java.util.Scanner;

class Question {
    int num1, num2, operator;
    int correctAnswer;

    public Question(int num1, int num2, char operator) {
        this.num1 = num1;
        this.num2 = num2;
        switch (operator) {
            case '+':
                correctAnswer = num1 + num2;
                break;
            case '-':
                this.correctAnswer = (num1 > num2) ? num1 - num2 : -1; // 确保减数小于被减数
                break;
            default:
                throw new IllegalArgumentException("Invalid operator");
        }
    }

    @Override
    public String toString() {
        return "题目: " + num1 + " " + operator + " " + num2 + ", 结果: " + correctAnswer;
    }
}

class QuizManager {
    private int totalQuestions;
    private int correctAnswers;
    private int incorrectAnswers;

    void startQuiz(Question[] questions) {
        for (int i = 0; i < totalQuestions; i++) {
            System.out.println(questions[i]);
            Scanner scanner = new Scanner(System.in);
            int userAnswer = scanner.nextInt();
            if (userAnswer == questions[i].correctAnswer) {
                correctAnswers++;
                System.out.println("回答正确!");
            } else {
                incorrectAnswers++;
                System.out.println("回答错误! 正确答案是: " + questions[i].correctAnswer);
            }
        }
    }

    void displayStats() {
        System.out.println("\n答题统计:");
        System.out.println("总共答对了: " + correctAnswers + " 题");
        System.out.println("总共答错了: " + incorrectAnswers + " 题");
    }
}

public class Main {
    public static void main(String[] args) {
        Random random = new Random();
        int minNum = 10;
        int maxNum = 99;
        Question[] questions = new Question[10];
        for (int i = 0; i < 10; i++) {
            int num1 = random.nextInt(maxNum - minNum + 1) + minNum;
            int num2 = random.nextInt(maxNum - minNum + 1) + minNum;
            char operator = random.nextBoolean() ? '+' : '-';
            questions[i] = new Question(num1, num2, operator);
        }

        QuizManager quizManager = new QuizManager();
        quizManager.totalQuestions = 10;
        quizManager.startQuiz(questions);
        quizManager.displayStats();
    }
}

在这个例子中，我们生成10道随机题目，每个题目包含两个两位数和一个加减运算符，并确保减法算式中被减数大于减数。`QuizManager`类负责控制用户输入和结果检查，最后会显示学生的答题统计。