Java随机数学方程生成随机答案

I am coding a problem where it will be x (+ or - or *) y =z and it will generate 4 possible answers for the user which has 1 good and 3 wrong answers. I made most of the code but I do not get how I make the same formula used again for Reponse() because right now when I execute the code, Equation() makes his own one and Reponse() does another different formula. Also I need to know how I can make sure that the code works by adding a system that will show a formula like 5 +5 = ? and the code will show 4 answers which has one good one.

我正在编码一个问题,它将是x(+或 - 或*)y = z,它将为用户生成4个可能的答案,其中有1个好的和3个错误的答案。我制作了大部分代码,但是我没有得到如何为Reponse()再次使用相同的公式,因为现在当我执行代码时,Equation()使用自己的代码,而Reponse()执行另一个不同的公式。另外我需要知道如何通过添加一个显示类似5 +5 =的公式的系统来确保代码的工作原理?并且代码将显示4个答案,其中一个答案很好。

here's the code:

这是代码:

    public class Equation {

    int x, y, z;


    public Equation() {
        Random r = new Random();
        x = r.nextInt(50) + 1;
        y = r.nextInt(50) + 1;
        z = 0;
        char operator = '?';

        switch (r.nextInt(3)) {
            case 0:
                operator = '+';
                z = x + y;
                break;
            case 1:
                operator = '-';
                z = x - y;
                ;
                break;
            case 2:
                operator = '*';
                z = x * y;
                ;
                break;
            default:
                operator = '?';
        }

        System.out.print(x);
        System.out.print(" ");
        System.out.print(operator);
        System.out.print(" ");
        System.out.print(y);
        System.out.print(" = ");
        System.out.println(z);

    }

}

and for Reponse() the one that generates the answers:

对于Reponse()生成答案的人:

    public class Reponse {
    Equation equ = new Equation();
    int a, b, c, d;
    char operator = '?';

    public Reponse() {
        Random r = new Random();
        switch (r.nextInt(4)) {

            case 0:
                a = r.nextInt(2 * equ.z);
                break;

            case 1:
                b = r.nextInt(2 * equ.z);
                break;

            case 2:
                c = r.nextInt(2 * equ.z);
                break;
            case 3:
                d = equ.z;
                break;
            default:
                operator = '?';
        }
    }
}

1 个解决方案

#1

This is because you are initializing the new instance of Equation class inside your Response class.

这是因为您正在Response类中初始化Equation类的新实例。

Equation equ = new Equation();

Whenever you'll do something like,

每当你做某事时,

Response r = new Response();

A new instance of Equation will be instantiated.

将实例化一个新的方程实例。

What you should be doing is as follows,

你应该做的是如下,

Change the Response class as follows:

更改Response类,如下所示:

public class Response {
    int a, b, c, d;
    char operator = '?';

    public Response(Equation equ) {
        Random r = new Random();
        switch (r.nextInt(4)) {

            case 0:
                a = r.nextInt(2 * equ.z);
                break;

            case 1:
                b = r.nextInt(2 * equ.z);
                break;

            case 2:
                c = r.nextInt(2 * equ.z);
                break;
            case 3:
                d = equ.z;
                break;
            default:
                operator = '?';
        }
    }
}

Note: I have deleted the instance of Equation from the class and am passing it to the constructor.

注意:我已从类中删除了Equation的实例,并将其传递给构造函数。

Create a new instance of Equation,

创建一个新的Equation实例,
```
Equation equ = new Equation();
```
Create a new instance of Response by passing above Equation instance,

通过传递上面的Equation实例创建一个新的Response实例,
```
Response r = new Response(equ);
```

Now, you can create multiple instances of Response class using the same instance of the Equation class that you instantiated.

现在,您可以使用实例化的Equation类的相同实例创建Response类的多个实例。

#1