基姆拉尔森计算公式计算星期

/*根据年月日计算星期*/
int CaculateWDay(int year,int mon,int day){
    /*一月 二月 视为上一年的13 14 月*/
    if(1==mon||2==mon) {
        mon += 12;
        year--;
    }
    int week = (day+ 2 * mon+3*(mon+1)/5+year+year/4-year/100+year/400)%7 + 1;
    return week;
}