乘法导师 Java 计划

Question

我正在编写一个遵循这些说明的程序：

Your little sister asks you to help her with her multiplication, and you decide to write a Java program that tests her skills. The program will let her input a starting number, such as 5. It will generate ten multiplication problems ranging from 5×1 to 5×10. For each problem she will be prompted to enter the correct answer. The program should check her answer and should not let her advance to the next question until the correct answer is given to the current question.

After testing ten multiplication problems, your program should ask whether she would like to try another starting number. If yes, your program should generate another corresponding ten multiplication problems. This procedure should repeat until she indicates no.

我有正确的代码来请求乘法部分，但我不太明白如何让程序询问用户是否要继续。

下面的代码有程序运行通过一次：

    package hw5;
    import java.util.Scanner;
    public class HW5 {
        public static void main(String[] args) {
            Scanner input = new Scanner(System.in);
            System.out.print("Enter number you would like to attempt: ");
            int start = input.nextInt();
            int mult;
            for (mult = 1; mult <= 10; mult++) {
                int num = start * mult;
                System.out.print(start + " x " + mult + " = ");
                int ans = input.nextInt();
                while (ans != num) {
                    System.out.print("Wrong answer, try again: ");
                    int ans2 = input.nextInt();
                    if (ans2 == num) {
                        break;
                    } 
                }

                //System.out.print("Would you like to do another problem? ");   

            }
        }
    }

当我取消对程序第 21 行的注释时 returns：

Enter number you would like to attempt: 1

1 x 1 = 1

Would you like to do another problem? 1 x 2 = 2

Would you like to do another problem? 1 x 3 =

etc...

如果我将第 21 行的代码放在 for 循环之外，程序运行会执行一次 for 循环，然后直接跳转到问题。

我该如何解决这个问题并成功完成说明？

Answer 1

这是我的做法：

    package hw5;
    import java.util.Scanner;
    public class HW5 {
    public static void main(String[] args) 
    {
        boolean wantsToContinue = true;
        while(wantsToContinue)
        {
            wantsToContinue = mathProblem();
        }
    }

    public static boolean mathProblem()
    {
        Scanner input = new Scanner(System.in);
        System.out.print("Enter number you would like to attempt: ");
        int start = input.nextInt();
        int mult;
        for (mult = 1; mult <= 10; mult++) {
            int num = start * mult;
            System.out.print(start + " x " + mult + " = ");
            int ans = input.nextInt();
            while (ans != num) {
                System.out.print("Wrong answer, try again: ");
                int ans2 = input.nextInt();
                if (ans2 == num) {
                    break;
                } 
            }

            //System.out.print("Would you like to do another problem? ");   

        }

        boolean wantsToContinue;
        //Ask if the user would like to do another problem here, set "wantsToContinue" accordingly
        return wantsToContinue;
    }
}

乘法导师 Java 计划

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