A.if x>0 then y=1 else if x=0 then y=0 else y= -1 B.if x>0 then y=1 else if x<0 then y= -1 else y=0 C.if x>=0 then if x=0 then y=0 else y= -1 else y=1 D.if x<>0 then if x<0 then y= -1 else y= 1 else y=0
A.abef B.cdef C.abgh D.cdgh
A.8 B.6 C.2 D.1