Question

该程序应显示计算总数的一系列分数（由用户确定）。它不允许我在程序中输入分数，只是它们所说的数量通常是无效的。

import java.util.*;
public class Fractions
{
    public static void main(String[] arg)
    {
        //------------------ declare ints and constants ----
        Scanner stdIn = new Scanner(System.in);

        int     fractions       = 0,
            count           = 1,
            fractionAdd     = 0;

        double  enteredFraction = 0;

        boolean inValid = false;
        //------------------- welcome msg -----------------------
        System.out.println("\n * * * Welcome to Fractions * * *\n");

        //--------------------- get input ----------------------
        System.out.print("Enter the number of fractions: ");
        fractions = stdIn.nextInt();

        if (fractions < 2 && fractions > 10)
            inValid = true;
        else
            inValid = true;

        while (inValid)
        {
            System.out.print(
                fractions + " is invalid, please re-enter ractions (2-10):  "
            );

            fractions = stdIn.nextInt();

            if (fractions < 2 && fractions > 10)
                inValid = true;

            else
                inValid = false;

        }
        while (count < fractions)
        {
            System.out.println(fractions + "+");
            fractions += count;

            while (fractions < count)
            {
                System.out.print(enteredFraction + " +");
                fractions ++;
            }

            if(enteredFraction <= fractions)
                System.out.println("Error, please re-enter number of fractions (2-10)");

        }

        //--------------------- end msg ---------------------------
        System.out.println("\nThanks for using the Fraction Adder program");

    } //end main
}//end program

Answer 1

    if (fractions < 2 && fractions > 10)
        inValid = true;
    else
        inValid = true;

我认为问题在这里。你设置了'inValid＆＃39;在这两种情况下都有标志。

Answer 2

您必须将$("#textarea").on('keydown',function(e){ if (e.ctrlKey && String.fromCharCode(e.which).toLocaleLowerCase() == 'b') { e.preventDefault(); var cursorPosition = $(this).prop("selectionStart"); this.value = this.value.substr(0, cursorPosition) + '-b- -.b-' + this.value.substr(cursorPosition); $(this).prop("selectionStart", cursorPosition + 3); $(this).prop("selectionEnd", cursorPosition + 3); } });更改为<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <textarea id="textarea"></textarea>以及

fractions += count;

总是fractions += count;您必须将其更改为if (fractions < 2 && fractions > 10) inValid = true; else inValid = true;

While-Loop并显示条形码作为输出

2 个答案: