【HDOJ】2133 What day is it

需要注意数据有效性。

 #include <stdio.h>

 #define isLeapYear(y) (y%4==0&&y%100!=0)||(y%400==0)

 int nums[][] = {{,,,,,,,,,,,,}, {,,,,,,,,,,,,}};
 char buf[][] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};

 int main() {
     int i, j, year, month, day, total;

     while (scanf("%d %d %d", &year, &month, &day) != EOF) {
         total = day;
         j = isLeapYear(year);
         if (month== || day==) {
             printf("illegal\n");
             continue;
         }
         for (i=; i<month; ++i)
             total += nums[j][i];
         if (month == ) {
             if (!j && day>) {
                 printf("illegal\n");
                 continue;
             }
             if (j && day>) {
                 printf("illegal\n");
                 continue;
             }
         }
         if ((month==||month==||month==||month==) && day>) {
             printf("illegal\n");
             continue;
         }
         for (i=; i<year; ++i) {
             if (isLeapYear(i))
                 total += ;
             else
                 total += ;
         }
         i = total % ;
         printf("%s\n", buf[i]);
     }

     return ;
 }