week2.java

java2程序设计使用教程（第2版） 作者：叶核亚 电子工业出版社 部分习题的代码 条例清晰 目标明确 海到尽头天作岸

//计算星期几

public class Week2
{
	public static void main(String args[])
	{
		int year=2002,month=6,day=8,total,week,i;
		boolean leap=false;
		leap=(year%400==0)|(year%100!=0)&(year%4==0);
		week=1;
		total=year-1980+(year-1980+3)/4;
		for(i=1;i<=month-1;i++)
		   switch(i)
		   {
		   	case 1:
		   	case 3:
		   	case 5:
		   	case 7:
		   	case 8:
		   	case 10:
		   	case 12:total+=31;break;
		   	case 4:
		   	case 6:
		   	case 9:
		   	case 11:total+=30;break;
		   	case 2:  if(leap)
		   	               total+=29;
		   	         else
		   	               total+=28;
		   	         break;
		   }
		   total=total+day;
		   week=(week+total)%7;
		   System.out.print("date "+year+'-'+month+'-'+day+" is ");
		   switch(week)
		   {		   
		   case 0:System.out.println("Sunday");break;
		   case 1:System.out.println("Monday");break;
		   case 2:System.out.println("Tuesday");break;
		   case 3:System.out.println("Wednesday");break;
		   case 4:System.out.println("Thursday");break;
		   case 5:System.out.println("Firday");break;
		   case 6:System.out.println("Saturday");break;
		   
		   }
	}
}