bool operator = (Query q){
     intQnum = q.Qnum();
     intPeriod = q.Period();
     intTimeOfReturn = q.TimeOfReturn();
 }
 friend bool operator< (Query q1, Query q2){
     return (q2.TimeOfReturn() < q1.TimeOfReturn())
            || ((q2.TimeOfReturn() == q1.TimeOfReturn())&&(q2.Qnum() < q1.Qnum()));
 }