weekday.java

计算 2008 年的 某天 时星期几。即你可以输入20081月1日就得出星期二.

import java.util.*;
public class WeekDay{
  public static void main (String[] args){ 
  int numberofmonth,numberofday,day = 0,r;boolean n ;
  
  System.out.println("class file was compiled by lichao");
  System.out.println("the program can calculate what date is the day you enter in 2008");
  
  Scanner keyboard = new Scanner(System.in);
  
  do{
    System.out.print("enter the month>");  
    numberofmonth = keyboard.nextInt();
    while (numberofmonth >= 13 || numberofmonth < 1 ){
  	  System.out.println("wrong input! try again!");
  	  System.out.print("enter the month>");
  	  numberofmonth = keyboard.nextInt();
  	
  	  }//输入月份并测验月份是否合法
  
  
    System.out.print("enter the day>");
    numberofday = keyboard.nextInt();  
    switch(numberofmonth){
	  case 1:
	  case 3:
	  case 5:
	  case 7:
	  case 8:
	  case 10:
	  case 12:
          if(numberofday > 31||numberofday < 1 ){
          System.out.println("wrong input! try again!");
          System.out.print("enter the day>");
          numberofday = keyboard.nextInt();  
            }
          } 
    switch(numberofmonth){
	  case 4:
	  case 6:
	  case 9:
	  case 11:
          if(numberofday > 30||numberofday < 1 ){
          System.out.println("wrong input! try again!");
          System.out.print("enter the day>");
          numberofday = keyboard.nextInt();  
             }
          }
   switch(numberofmonth){
 	  case 2:
          if(numberofday > 29||numberofday < 1){
          System.out.println("wrong input! try again!");
          System.out.print("enter the day>");
          numberofday = keyboard.nextInt();  
            }
        }//输入日子并测验其输入是否正确
        
        
   switch(numberofmonth){
         case 1: day = numberofday - 1;break;
         case 2: day = 30+numberofday;break;
         case 3: day = 30+29+numberofday;break;
         case 4: day = 30+29+31+numberofday;break;
         case 5: day = 30+29+31+30+numberofday;break;
         case 6: day = 30+29+31+30+31+numberofday;;break;
         case 7: day = 30+29+31+30+31+30+numberofday;;break;
         case 8: day = 30+29+31+30+31+30+31+numberofday;break;
         case 9: day = 30+29+31+30+31+30+31+31+numberofday;break;
         case 10: day = 30+29+31+30+31+30+31+31+30+numberofday;break;
         case 11: day = 30+29+31+30+31+30+31+31+30+31+numberofday;break;
         case 12: day = 30+29+31+30+31+30+31+31+30+31+30+numberofday;break;
        } //计算输入日子和1月1日相隔的天数
        
   r = day%7; String x = "\0",month = "\0";
   switch(r){ 
 	  case 0:x ="Tuesday";break;
 	  case 1:x ="Wednesday";break;
 	  case 2:x ="Thursday";break;
 	  case 3:x ="Friday";break;
 	  case 4:x ="Saturday";break;
 	  case 5:x ="Sunday";break;
 	  case 6:x ="Monday";break;
 	  } //求余数对应星期,并将余数对应转换成用英语表示的星期
   switch(numberofmonth){
 	  case 1: month = "January";break;
 	  case 2: month = "February";break;
 	  case 3: month = "March";break;
 	  case 4: month = "April";break;
 	  case 5: month = "May";break;
 	  case 6: month = "June";break;
 	  case 7: month = "July";break;
 	  case 8: month = "August";break;
 	  case 9: month = "September";break;
 	  case 10: month = "October";break;
 	  case 11: month = "November";break;
 	  case 12: month = "December";break;
 	  } //将月份的阿拉伯数字转换成英语
   System.out.println(month+" "+numberofday+","+" "+"2008 is "+x);
   System.out.println("Caculate again? (true/false)");  
   n = keyboard.nextBoolean();  
   } while(n);
  }
}