782int QCDateKey(const datetime value)783{784   MqlDateTime t;785   TimeToStruct(value, t);786   return t.year * 10000 + t.mon * 100 + t.day;787}788datetime QCMidnight(const datetime value)789{790   MqlDateTime t;791   TimeToStruct(value, t);792   t.hour = 0;793   t.min = 0;794   t.sec = 0;795   return StructToTime(t);796}797int QCSecondOfDay(const datetime value)798{799   MqlDateTime t;800   TimeToStruct(value, t);801   return t.hour * 3600 + t.min * 60 + t.sec;802}803string QCUpper(string value)804{805   StringToUpper(value);806   return value;807}808string QCKey(const string suffix)809{810   return QCG.key_prefix + suffix;811}812void QCInitGuardState(const string symbol, const long magic_base, const int core_count)813{814   ZeroMemory(QCG);815   QCG.symbol = symbol;816   QCG.magic_base = magic_base;817   QCG.core_count = core_count;818   QCG.lock_day = -1;819   string hash_source = AccountInfoString(ACCOUNT_SERVER) + "|" + symbol;820   uint hash = 2166136261;821   for (int i = 0; i < StringLen(hash_source); ++i)822      hash = (hash ^ (uint)StringGetCharacter(hash_source, i)) * 16777619;823   QCG.key_prefix = "QX." + (string)AccountInfoInteger(ACCOUNT_LOGIN) + "." + (string)hash;824}825// EU last-Sunday 01:00 UTC reference clock, fixed UTC+2 / UTC+3.826int QCReferenceUTCOffset(const datetime utc)827{828   MqlDateTime t;829   TimeToStruct(utc, t);830   t.mon = 3;831   t.day = 31;