结对合作 出题并判断对错

package tools;

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

public class problem {

    public static void main(String[] args) {
        /**
         * 一共循环10次。
         */
        int rightNum = 0;//正确次数
        int wrongNum = 0;//错误次数
        for (int i =1; i <= 10; i++) {
            System.out.println("请计算第" + i + "道题：");// 做到第几题，循环输出
            int number1 =(int) (Math.random() * 10);
            int number2 =(int) (Math.random() * 10);
            Random num = new Random();// 生成随机运算符
            int index = num.nextInt(3) + 1;
            char[] fuhaos = { '+', '-', '*', '/' };
            String fuhao = String.valueOf(fuhaos[index]);
            Scanner scan = new Scanner(System.in);
            if (fuhao.equals("+")) { // 进行加法运算
                System.out.println(number1 + "+" + number2 + "=");
                int input = scan.nextInt();
                int sum = number1 + number2;
                if (sum==input) {
                    System.out.println("正确");
                    rightNum++;
                } else {
                    System.out.println("错误");
                    wrongNum++;
                }
                System.out.println("正确答案是:" + sum);
            }else if (fuhao.equals("-")) { // 进行减法运算
                System.out.println(number1 + "-" + number2 + "=");
                int input = scan.nextInt();
                int sum = number1 - number2;
                if (sum==input) {
                    System.out.println("正确");
                    rightNum++;
                } else {
                    System.out.println("错误");
                    wrongNum++;
                }
                System.out.println("正确答案是:" + sum);
            }else if (fuhao.equals("*")) { // 进行乘法运算
                System.out.println(number1 + "*" +number2 + "=");
                int input = scan.nextInt();
                int sum = number1 * number2;
                if (sum==input) {
                    System.out.println("正确");
                    rightNum++;
                } else {
                    System.out.println("错误");
                    wrongNum++;
                }
                System.out.println("正确答案是:" + sum);
            }else {                     // 进行除法运算
                System.out.println(number1 + "/" + number2 + "=");
                int input = scan.nextInt();
                int sum = number1 / number2;
                if (sum==input) {
                    System.out.println("正确");
                    rightNum++;
                } else {
                    System.out.println("错误");
                    wrongNum++;
                }
                System.out.println("正确答案是:" + sum);
            }
        }
        System.out.println("做对" + rightNum + "题");
        System.out.println("做错" + wrongNum + "题");
    }
}

　　　　结对组合：林莉  和  宫丽君