四则运算题目生成程序（基于控制台）

一：题目描述

1.自动生成小学四则运算题目

  2.用户能够选择数值范围以及题目个数

  3.程序一次运行的题目不能重复

  4.生成的题目存入执行程序的当前目录下的Exercises.txt文件、答案存入Answers.txt文件

  5.程序支持对给定的题目文件和答案文件，判定答案中的对错并进行数量统计，并会输出所有题目中重复的题目，输入参数如下：

     Myapp.exe -e <exercisefile>.txt -a <answerfile>.txt -o Grade.txt

 

    统计结果输出到文件Grade.txt，格式如下：

 

    Correct: 5 (1, 3, 5, 7, 9)

    Wrong: 5 (2, 4, 6, 8, 10)

    Repeat:2

    RepeatDetail:

   (1)   2,45+32  Repeat 3,32+45                    

   (2)   5,3+(2+1)  Repeat 7,1+2+3

二：需求分析

1.生成四则运算题目，能够给定题目数量难度

2.题目及正确答案以文件形式保存

2.做答，并能判断是否正确，列出正确和错误题号

三：代码实现

1.操作数及运算符号的随机生成类num类

2.生成中缀表达式转成后缀表达式计算calculate类

3.程序入口类entrance类

 

后缀表达式计算

public String dealEquation(String equation){
       String [] arr = equation.split(",");                                    
       List<String> list = new ArrayList<String>();                            
       
       
       for (int i = 0; i < arr.length; i++) {                                   
           int size = list.size();
           switch (arr[i]) {
           case "+": Num a = new Num(list.remove(size-2)).add(new Num(list.remove(size-2))); 
           list.add(a.toString());     
           break;
           case "-": Num b = new Num(list.remove(size-2)).sub(new Num(list.remove(size-2))); 
           list.add(b.toString());     
           break;
           case "*": Num c = new Num(list.remove(size-2)).muti(new Num(list.remove(size-2))); 
           list.add(c.toString());     
           break; 
           case "÷": Num d = new Num(list.remove(size-2)).division(new Num(list.remove(size-2))); 
           list.add(d.toString());    
           break;
           default: list.add(arr[i]);     
           break;                                    
           }
       }

题目答案写入文件及回答的答案正确性判断

public static void run(){
        
        String[] answer=new String[n];
         try{
                BufferedWriter writer = new BufferedWriter(new FileWriter(new File(ename),true));
                BufferedWriter awriter = new BufferedWriter(new FileWriter(new File(aname),true));
                for(int i=0;i<n;i++){
                    Request req = new Request(); 
                    req.create(r);
                    Node no = new Node();
                    no.requestToNode(req);
                    System.out.print(i+":"+req.getStr()+'\n');
                    writer.write(i+":"+req.getStr());
                    writer.newLine();
                    answer[i]=req.getAnswer();
                    awriter.write(i+":"+req.getAnswer());
                    awriter.newLine();
                }
                writer.close();
                awriter.close();
            }catch(Exception e){
                e.printStackTrace();
            }    
         System.out.println("出题成功，请开始答题\n");
         Scanner scanner = new Scanner(System.in);
         String[] myanswer=new String[n];
            for(int i = 0;i<n;i++){
                myanswer[i] = scanner.next();
            }
            
        String rightAnswerResport = "Correct: ",rightAnswerList = "正确的题号";//构造正确部分呢过的答题报告
        String wrongAnswerResport = "Wrong",wrongAnswerList = "错误的题号";//构造错误部分呢过的答题报告
        int rightNumber = 0,wrongNumber = 0;//记录正确和错误的个数
        for(int i = 0;i<n;i++){//开始校验用户的回答
            if(myanswer[i].equals(answer[i])){
                rightNumber++;
                rightAnswerList = rightAnswerList+ (i+1)+",";
            }else{
                wrongNumber++;
                wrongAnswerList = wrongAnswerList + (i+1) +",";
                    }

                }
                System.out.print(rightNumber+"道题正确"+"    "+rightAnswerList+'\n');
                System.out.print(wrongNumber+"道题错误"+"    "+wrongAnswerList+'\n');

    }

四：测试运行

五：小节

代码繁杂，有待优化。

 

git地址：https://git.coding.net/HHWORLD/Exp1.git