BARSLASTCOUNT函数的疑问

例：
AA:HHV(H,20),COLORRED;
BB:LLV(L,20),COLORCYAN;
CROSS(H,REF(AA,1)),BK;
CROSS(REF(BB,1),L),SK;
CROSS(H,REF(AA,1)),BP;
CROSS(REF(BB,1),L),SP;
SETSIGMAXNUM(2);
AUTOFILTER;
//一根K线上最多出现两个信号