Buy stop sell stop for optimize

#1
Hi , Friends

I am trying optimize some afl. Buy sell code


Buy=Cross (SK,SD) ;
Sell=Cross(SD,SK) ;

Short = Sell;
Cover = Buy;

How can I add Buystop and sellstop

Buystop : When cross SD,SK and SK > 50

Sellstop : When cross SK,SD and SK<50