Question

好吧我觉得这可能很难解释，因为我往往是我班上唯一遇到这个问题的人，但基本上我现在正在学习Java编程。我有一个问题，基本上我必须扫描变量的值然后将该变量带入while循环，问题是程序在启动时不会启动while循环。它让我继续输入数字，但这是问题，它保持扫描数字，但它只需要扫描一次，它不会进入循环。这是程序

import java.util.Scanner;
public class Week05_NelsonPimentel_Assignment {
    public static void main(String args[]){
        int veraq;
        int times = 0;
        Scanner input = new Scanner(System.in);


        System.out.println("Please enter how many coins you have");

        veraq = input.nextInt();
        while(veraq>0){


            firstmachine(veraq);
            howmanytimesplayed(times);
            secondmachine(veraq);
            howmanytimesplayed(times);
            thirdmachine(veraq);
            howmanytimesplayed(times);

        }


            System.out.println("You were able to play this many times before running out of quarters: " +times);



        }





    static int howmanytimesplayed(int times)
    {
        times++;
        return times;
    }

    static int firstmachine(int veraq)
    {
        int times = 0;


        if(times == 33){
            veraq = veraq + 24;
            times = 0;
            System.out.println("Congradulations! On machine number one you have won $6.25!! You have this many coins left: " +veraq);
            return veraq;
        }
        else if( times != 33)
        {
            veraq = veraq - 1;
            times++;
            return veraq;
        }
        return 0;
    }

    static int secondmachine(int veraq)
    {
        int times = 0;

        if(times == 99){
            veraq = veraq + 74;

            times = 0;
            System.out.println("Congradulations! On machine number two you have won $18.75!! You have this many coins left: " +veraq);
            return veraq;
        }
        else if( times != 99)
        {
            veraq = veraq - 1;
            times++;
            return veraq;
        }

        return 0;
    }


    static int thirdmachine(int veraq)
    {
    int times = 0;

        if(times == 9){
            veraq = veraq + 6;
            times = 0;**enter code here**
            System.out.println("Congradulations! On machine number three you have won $1.75!! You have this many coins left: " +veraq);
            return veraq;
        }
        else if( times != 9)
        {
            veraq = veraq - 1;
            times++;
            return veraq;
        }
        return 0;
    }
}

Answer 1

你的程序不是在不断地扫描数字，程序中的while循环永远不会被终止，即它在无限循环中运行。

' int '是Java中的原始数据类型。当您调用方法firstmachine(veraq);并使此方法对变量 veraq 执行某些操作时，这些更改将不会反映在 veraq 变量的范围内主要方法。因此，如果你传递 veraq 的正值，它基本上永远不会小于0，你的while循环将永远运行。此外，您的程序是以这样的方式编写的，即不会打印任何内容，从而让您觉得您的程序不断扫描数字。

您应该了解按值调用的内容以及通过引用调用的内容。然后，您应该了解这些概念如何与Java中的方法传递参数相关。祝你好运：）

Java编程，程序不会通过扫描程序进入while循环

1 个答案: