Question

我的代码出了什么问题？出于某种原因，我一天休息一天？例如，今天是2013年的第26天，它是星期二，但该计划告诉我它是星期三。我正在使用Zeller的同余算法。

import javax.swing.JOptionPane;
public class zeller {
    public static void main(String[] args) {
        String yearString = JOptionPane.showInputDialog("Enter the year:");

        int year = Integer.parseInt(yearString);

        String monthString = JOptionPane.showInputDialog("Enter the month (3-12)(January and Feburary are 13 and 14):");
        int month = Integer.parseInt(monthString);

        String dayString = JOptionPane.showInputDialog("Enter the day 1-31: ");  
        int day = Integer.parseInt(dayString);

        switch (month) {
            case 13:  monthString = "January";
                break;
            case 14:  monthString = "February";
                break;
            case 3:  monthString = "March";
                break;
            case 4:  monthString = "April";
                break;
            case 5:  monthString = "May";
                break;
            case 6:  monthString = "June";
                break;
            case 7:  monthString = "July";
                break;
            case 8:  monthString = "August";
                break;
            case 9:  monthString = "September";
                break;
            case 10: monthString = "October";
                break;
            case 11: monthString = "November";
                break;
            case 12: monthString = "December";
                break;
            default: monthString = "Invalid month";
                break;
        }

        int j = year / 100;
        int k = year % 100 ;
        double h = (day + ((26*(month + 1)) / 10) + k + (k / 4) +(j / 4) + (5 * j)) % 7;
        int h1 = (int)h;

        switch (h1) {
            case 0:  dayString = "Saturday";
                break;
            case 1:  dayString = "Sunday";
                break;
            case 2:  dayString = "Monday";
                break;
            case 3:  dayString = "Tuesday";
                break;
            case 4:  dayString = "Wednesday";
                break;
            case 5:  dayString = "Thursday";
                break;
            case 6:  dayString = "Friday";
                break;

            default: monthString = "Invalid month";
                break;
        }

        System.out.println("Day of the week is: " + dayString);
    }
}

Answer 1

1月和2月分别计为上一年的第13个月和第14个月，所以如果您希望用户输入1月或2月的实际月份1或2，您可以添加如下代码：

if (month == 1 ){
    month = 13;
     year -=1;
 }
else if (month == 2) {
     month = 14;
     year -=1;
}

Answer 2

如果是1月或2月，您需要修改年份。关于维基百科的解释：

人们可以很容易地看到，在给定的一年，3月1日（如果那是一个星期六，然后3月2日）是一个很好的考试日期;在一个给定的世纪，最佳考试年份是100的倍数。泽勒使用十进制算术，发现使用J和K很方便代表年份。但是当使用计算机时，它更简单处理修改后的年份Y，即1月份的 Y - 1 2月：

我修改了你的代码，如下所示：

import javax.swing.JOptionPane;

public class zeller {
    public static void main(final String[] args) {

        String yearString = JOptionPane.showInputDialog("Enter the year:");

        int year = Integer.parseInt(yearString);

        String monthString =
            JOptionPane.showInputDialog("Enter the month (3-12)(January and Feburary are 13 and 14):");
        int month = Integer.parseInt(monthString);

        String dayString = JOptionPane.showInputDialog("Enter the day 1-31: ");
        int day = Integer.parseInt(dayString);

        switch (month) {
        case 14:
            year--;
            monthString = "January";
            break;
        case 13:
            year--;
            monthString = "February";
            break;
        case 3:
            monthString = "March";
            break;
        case 4:
            monthString = "April";
            break;
        case 5:
            monthString = "May";
            break;
        case 6:
            monthString = "June";
            break;
        case 7:
            monthString = "July";
            break;
        case 8:
            monthString = "August";
            break;
        case 9:
            monthString = "September";
            break;
        case 10:
            monthString = "October";
            break;
        case 11:
            monthString = "November";
            break;
        case 12:
            monthString = "December";
            break;
        default:
            monthString = "Invalid month";
            break;
        }
        int j = year / 100;
        int k = year % 100;
        double h = (day + ((13 * (month + 1) / 5)) + k + (k / 4) + (j / 4) + (5 * j)) % 7;
        int h1 = (int) h;
        switch (h1) {
        case 0:
            dayString = "Saturday";
            break;
        case 1:
            dayString = "Sunday";
            break;
        case 2:
            dayString = "Monday";
            break;
        case 3:
            dayString = "Tuesday";
            break;
        case 4:
            dayString = "Wednesday";
            break;
        case 5:
            dayString = "Thursday";
            break;
        case 6:
            dayString = "Friday";
            break;

        default:
            monthString = "Invalid month";
            break;
        }

        System.out.println("Day of the week is: " + dayString);

    }
}

Answer 3

来自维基百科，

在此算法中，1月和2月计为上一年的第13和第14个月。例如。如果是2010年2月2日，则算法将日期计为2009年第14个月的第二天（2009年2月14日以DD / MM / YYYY格式）。

因此，您的代码在技术上没有任何问题;在2013年2月26日（今天）作为2013年第14个月的第26天实际计算2014/02年/ 的日期。

我的代码出了什么问题？ Zeller的同余算法代码

3 个答案: