缠主图

N1:=5;
顶周期:=HHV(H,N1);
底周期:=LLV(L,N1); 
底:=L=底周期;
顶:=H=顶周期;
DRAWLINE(底,L,顶,H,0),COLORYELLOW,LINETHICK3;
DRAWLINE(顶,H,底,L,0),COLORYELLOW,LINETHICK3;