java - 多个方法的全局Int变量方法

Question

我必须建立一个数学程序，根据用户的年级水平向他们提供随机问题，如果他们做得好，就提高难度。我在这里设置了运行问题的代码，如果它们满足要求，它会显示更难的问题，但是如果我用“i”来确定他们如何完成成员(member)问题，如果分开，程序将运行更难的问题然后回去完成更简单的问题

所以基本上我尝试为全局“i”编写一个所有其他方法都会使用的方法，但是当我用该方法替换“i”时，它会停止计数并继续无限地显示问题，我不知道如何解决这个问题。

import java.util.Scanner; 
import java.util.*;
import java.util.Date; 

public class Quiz {

    public static void main(String[] args) {

        int answer;
        int correct;
        double current_score = 100.00;
        //      int i = 0;

        while (questionsDone() < 10) { // start of question loop

            int random = (int) (Math.random() * 9 + 0);
            int random2 = (int) (Math.random() * 9 + 0);

            System.out.print("What is the sum of" + " ");
            System.out.print(random);
            System.out.print(" + " + random2 + " ");
            System.out.print("=" + " ");

            Scanner scan = new Scanner(System.in);
            //answer
            answer = scan.nextInt();

            correct = random + random2;

            if (answer == correct) { // start of result display
                System.out.println("You are correct");
            } else if (answer != correct) {
                System.out.println("That wasn't right");
                current_score = (current_score - 10.00);
            }

            System.out.println("Your current percentage is " + current_score); // end of result display

            // i++; // raise number of questions given by 1
            if (questionsDone() == 5 && current_score >= 75) { // code to move up or down year level
                System.out.println("You are doing well! Let's increase the difficulty a little");
                Year1_10Questions();
            }

        }

    }

    public static void Year1_10Questions() {

        int i = 0;
        int answer;
        int correct;
        double current_score = 100.00;
        while (i < 10) { // start of question loop

            int random = (int) (Math.random() * 9 + 0);
            int random2 = (int) (Math.random() * 9 + 0);
            int random3 = (int) (Math.random() * 2 + 1);

            String operator = "";
            switch (random3) {
                case 1:
                    operator = "+";
                    break;
                case 2:
                    operator = "-";
                    break;
            }

            System.out.print("What is the sum of ");
            System.out.print(" " + random + " ");
            System.out.print(operator + " ");
            System.out.print(random2 + " ");

            Scanner scan = new Scanner(System.in);
            //answer
            answer = scan.nextInt();

            if (random3 == 1) {
                correct = random + random2;

                if (answer == correct) { // start of result display
                    System.out.println("You are correct");
                } else if (answer != correct) {
                    System.out.println("That wasn't right");
                    current_score = (current_score - 10);

                }
            } else if (random3 == 2) {
                correct = random - random2;

                if (answer == correct) { // start of result display
                    System.out.println("You are correct");
                } else if (answer != correct) {
                    System.out.println("That wasn't right");
                    current_score = (current_score - 10);

                }

            }
            System.out.println("Your current percentage is " + current_score); // end of result display

            i++; // raise number of questions given by 1

        }

    } // end of year 1_10 questions

    public static int questionsDone() {
        int i = 0;
        i++;
        return i;
    }

}

Answer 1

由于所有方法都在同一个类中，因此您可以在类级别定义 i:

public class Quiz {
    static int i;
    ...
}