软件工程个人作业01

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

public class opation {
     
    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        System.out.println("请输入你要打印题目的数量");
        int count=scanner.nextInt();
        int character=0;
        int num1=0;
        int num2=0;
        int correct=0;
        int error=0;
        
        String operat=null;
        double result[]=new double[count];
        Random random = new Random();
        for(int i=0;i<count;i++) {
            
            character=random.nextInt(4)%4+1; 
                num1 = random.nextInt(60)%60+1;
            if(character==2||character==4) {
                if(num1==0)
                    num1=num1+2;
                num2=(int)random.nextInt(num1)%(num1)+1; 
                if(num2==0) {
                    num2++;
                }
            }
            else {
                num2= random.nextInt(60)%60+1;
            }
            String number1=String.valueOf(num1);
            String number2=String.valueOf(num2);
            if(character==1) {
                operat="第("+(i+1)+")题"+number1+"+"+number2+"=";
                result[i]=num1+num2;
            }
            else  if(character==2) {
                operat="第("+(i+1)+")题"+number1+"-"+number2+"=";
                result[i]=num1-num2;
            }
            else  if(character==3) {
                operat="第("+(i+1)+")题"+number1+"*"+number2+"=";
                result[i]=num1*num2;
            }
            else {
                operat="第("+(i+1)+")题"+number1+"/"+number2+"=";
                result[i]=(double)num1/(double)num2;
            }
            if((result[i]>100)||(IsXiaoshu(result[i])>3)) {
                i--;
            }
            else {
                System.out.print(operat);
                double result2=scanner.nextDouble();
                if(result2==result[i]) {
                    correct++;
                }
                else 
                    error++;
            }
        }
        System.out.println("恭喜你，答对了"+correct+"道题，打错了"+error+"道题");

    }
    static int IsXiaoshu(double result) {
        int result2=(int)result;
        double xiaoshu=result-result2;
        String result3=String.valueOf(xiaoshu);
        
        return result3.length();
    }

}

（2）设计思想

     先用随机函数生成第一个和第二个操作数和运算符号，然后转化成计算式计算出正确答案，然后判断答案是否超过100和判断结果的小数位数，如果不超过100和小数位的长度为0则输出，如果不是则重新循环生成操作数和运算符号。

（3）运行结果截图