java - 星期几、java 和 Zeller 的同余!

Question

我正在根据一本教科书进行这个编程练习，其中给我们提供了一种计算星期几的算法，称为泽勒同余。那么你认为我可以获得与教科书中运行的示例相同的输出吗？它们与 2002 年第 3 个月和第 26 个月的某一天一致。样本会读回星期二。我已经进行了几个小时的修改和重写，但在周二之前却一事无成!

这是 Java 综合教科书 8e 的第 133 页，如果有人有的话...我是初学者，非常欢迎建设性的反馈!

Zeller's Congruence

您的建议将不胜感激:

import java.util.Scanner;

public class DayOfTheWeek {

   public static void main(String[] args) {

   // Set up the scanner...
   Scanner input = new Scanner(System.in);

   // Set up the day's of the week with 0 being Sat as per algorithm.           
   final String[] DAY_OF_WEEK = {"Saturday", "Sunday", "Monday", 
       "Tuesday", "Wednesday", "Thursday", "Friday"};

   // Get the year       
   System.out.print("Enter the year (e.g., 2002): ");             
   int year = input.nextInt();

   // Get the month
   System.out.print("Enter the month 1-12: ");  
   int month = input.nextInt();

   // Get the day
   System.out.print("Enter the day 1-31: ");  
   int day = input.nextInt();

   // According to the algorithm Jan is 13 & Feb 14...
   if (month == 1) month = 13;
   else if (month == 2) month = 14;

   // j Is the century.
   int j = year / 100;

   // k Is the year of the century.
   int k = year % 100 ;

   // Calculate
   double h = (month + ((26*(month + 1)) / 10) + k + (k / 4) +
           (j / 4) + (5 * j)) % 7;

   // Cast answer back to integer to get result from array
   int ans = (int)h;

   // Print result
   System.out.println("Day of the week is: " + DAY_OF_WEEK[ans]);

   }
}

Answer 1

看起来这行代码是错误的:

double h = (month + ((26*(month + 1)) / 10) + k + (k / 4) +
(j / 4) + (5 * j)) % 7;

该公式将日添加到第一个表达式中，而不是月。所以它应该看起来像这样:

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