int __month_to_secs(int month, int is_leap) {
  static const int secs_through_month[] = {
      0,           31 * 86400,  59 * 86400,  90 * 86400,
      120 * 86400, 151 * 86400, 181 * 86400, 212 * 86400,
      243 * 86400, 273 * 86400, 304 * 86400, 334 * 86400};
  int t = secs_through_month[month];
  if (is_leap && month >= 2)
    t += 86400;
  return t;
}