public class Week2
{
    public static void main(String args[]) 
    {
        int year=2006,month=1,day=28,total,week,i;
        boolean leap=false;
        leap = (year%400==0)| (year%100!=0) & (year%4==0);
        week =1;                                 //起始日 1979-12-31是星期一
        total = year-1980+(year-1980+3)/4;       //求平(閏)年累計(jì)的總天數(shù)
        for (i=1;i<=month-1;i++)                 //當(dāng)年的累計(jì)天數(shù)
            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;                       //當(dāng)月的天數(shù)
        week = (week+total) % 7;                 //求得星期幾
        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("Friday");   break;
            case 6: System.out.println("Saturday"); break;
        }
    }
}

/* 
程序運(yùn)行結(jié)果如下：
date 2006-1-28 is Saturday

*/