Java程序高低游戏

Question

我用 jQuery 写了这个，但是循环不正确，我看不到我的错误？当用户输入-99时它并没有结束？也不计算最高和最低数字？

import java.util.Scanner;

public class LargestandSmallest
{

    public static void main (String [] args)
    {

        //Create a Scanner object for the keyboard input
        Scanner keyboard = new Scanner(System.in);

        //Declare local variable
        double number;


        //Explain what the program does
        System.out.println ("This program will ask you to enter in a series of");
        System.out.println ("numbers, and then will display the lowest and");
        System.out.println ("highest numbers, out of what you enter, until you input");
        System.out.println ("the value indicated to end the program.");


        //Have the user input a series of numbers and continue processing 
        //until the user enters -99
        System.out.println ("Please enter a number: (or -99 to end the program).");
        number = keyboard.nextDouble();

        //Display the table headings
        System.out.println ("Lowest\tHighest");
        System.out.println ("------------------");

        //Call the method to caluclate the highest and lowest numbers
        calculateLowHigh(number);
    }

    //Module called calculateTemp
    public static void calculateLowHigh(double number)
    {  

        //Declare local calculation variables
        double highestNumber = 0;
        double lowestNumber = 0;

        //Set the parameters for running the loop
        while (number != -99)
        {
            for(number = 0; number < 5; number++)
            {

                //Calculate the lowest and highest numbers entered
                if (number > highestNumber) {
                    highestNumber = number;
                }

                if (number < lowestNumber) {
                    lowestNumber = number; 
                }

            }  
        }

        //Display the results
        System.out.println (lowestNumber + "\t\t" + highestNumber);


     }

}

Answer 1

您的问题是，在 calculateLowHigh 中，您将 number 变量用于两种不同的用途。它是将用户输入的数字传递给此方法的参数；但您还使用它作为 for 循环内的循环索引。也许您应该出于一个或另一个目的使用不同的变量。更好的是，完全放弃 for 循环 - 它似乎没有做任何事情。

此外，while循环应该在main中完成，而不是在calculateHighLow中完成，否则用户将只能有机会输入一个数字一次。