extern int MAGICTerminal=101;
extern double LOTSize=0.10;
extern string ORDERComment="Order Comment Text";
//TOTAL Count..
int btotal=0; int stotal=0; int ticket=0; double closelots=0; bool xbool;
for( int cnt=OrdersTotal()-1;cnt>=0;cnt--)
{
xbool=OrderSelect(cnt, SELECT_BY_POS, MODE_TRADES);
if(OrderType()==OP_BUY && OrderMagicNumber()==MAGICTerminal && OrderSymbol()==Symbol()){btotal++; ticket=OrderTicket(); closelots=OrderLots();}
if(OrderType()==OP_SELL && OrderMagicNumber()==MAGICTerminal && OrderSymbol()==Symbol()){stotal++; ticket=OrderTicket(); closelots=OrderLots();}
}// END TOTAL count..
if(WHATEVER YOUR CONDITION FOR A BUY)
{
if(btotal>0){OrderClose(ticket,closelots,Bid,3,CLR _NONE);}
ticket=OrderSend(Symbol(),OP_BUY,LOTSize,Ask,3,0,0 ,ORDERComment,MAGICTerminal,0,Magenta);
}
if(WHATEVER YOUR CONDITION FOR A SELL)
{
if(stotal>0){OrderClose(ticket,closelots,Ask,3,CLR _NONE);}
ticket=OrderSend(Symbol(),OP_SELL,LOTSize,Bid,3,0, 0,ORDERComment,MAGICTerminal,0,Lime);
}