关于c ++：使用Windows注册表寻找下一个“夏令时”

Looking for the next “Daylight Saving Time” using the Windows registery

使用Windows注册表查找下一个"夏令时"。

我必须使用旧版本的Borland C ++。

夏令时的想法随绝对日期而变化

登记处的"欧洲标准时间"表示"夏令时"发生在3月的第5次发生，这是假的，因为它是第4次发生。 MSDN doc。

所以当我这样做时：

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void findDate(int year, SYSTEMTIME systemTime)
{
struct tm timestr;
int occ = 0;
bool found = false;

timestr.tm_year = year - 1900;
timestr.tm_mon = systemTime.wMonth - 1;
timestr.tm_mday = 0;
timestr.tm_hour = systemTime.wHour;
timestr.tm_min = systemTime.wMinute;
timestr.tm_sec = systemTime.wSecond;
timestr.tm_isdst = 0;

while((timestr.tm_mday <= 31 && !found)) {
timestr.tm_mday += 1;
time_t standard = mktime(&timestr);
struct tm * temp = localtime(&standard);
if(temp->tm_wday == systemTime.wDayOfWeek) {
occ++;
}

if(occ >= sysemTime.wDay) {
found = true;
printf("

Found: %s", asctime( &timestr ));
}
}
}

int main(int argc, char* argv[])
{
// Get the timezone info.
TIME_ZONE_INFORMATION TimeZoneInfo;
GetTimeZoneInformation( &TimeZoneInfo );
DYNAMIC_TIME_ZONE_INFORMATION TimeZoneInfoDyn;

printf("

StandardDate %d wDay%d wDayOfWeek%d %d %d %d", TimeZoneInfo.StandardDate.wMonth, TimeZoneInfo.StandardDate.wDay, TimeZoneInfo.StandardDate.wDayOfWeek, TimeZoneInfo.StandardDate.wHour, TimeZoneInfo.StandardDate.wMinute, TimeZoneInfo.StandardDate.wSecond);
printf("
DaylightDate %d wDay%d wDayOfWeek%d %d %d %d", TimeZoneInfo.DaylightDate.wMonth, TimeZoneInfo.DaylightDate.wDay, TimeZoneInfo.DaylightDate.wDayOfWeek, TimeZoneInfo.DaylightDate.wHour, TimeZoneInfo.DaylightDate.wMinute, TimeZoneInfo.DaylightDate.wSecond);

findDate(2017, TimeZoneInfo.StandardDate);
findDate(2018, TimeZoneInfo.DaylightDate);
getchar();
return 0;

}

它显示：

1 2	Found: Sun Oct 29 03:00:00 2017 Found: Sun Apr 01 03:00:00 2018

代替：

1 2	Found: Sun Oct 29 03:00:00 2017 Found: Sun Mar 25 03:00:00 2018

我究竟做错了什么？