6 return (year % 4 == 0 && year % 100 != 0 || year % 400);
11 int day_plasminus(int * y, int * m, int * d, char mark)
15 { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
16 { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }};
31 *d = day[isleap(*y)][*m];
36 if (*d != day[isleap(*y)][*m]) {