主题：为什么只显示多头信号，没显示空头信号呀

RSV:=(CLOSE-LLV(LOW,N))/(HHV(HIGH,N)-LLV(LOW,N))*100;
K:=SMA(RSV,P1,1);
D:=SMA(K,P2,1);
J:=3*K-2*D;

long:ma(c,55);

if o>long and  ref(c,10)<long and CROSS(D,K) then begin
   buy(holding=0,1,market);
end;
if cross(k,d) then begin
   sell(1,0,market);
 end;
if  o<long  and ref(c,10)>long  AND CROSS(K,D)  then  begin

buyshort(holding=1,1,market);
end;
if  cross(d,k) then begin
sellshort(1,0,market);
end;