;对分查表法
data segment
s1 db 00,01,02,03,04,05,06,07,08,09
   db 10,11,12,13,14,15,16,17,18,19
   db 20,21,22,23,24,25,26,27,28,29
count equ $-s1
s2 db ?
data ends
stack segment stack
s3 db 20 dup(?)
stack ends
code segment
assume cs:code,ds:data,es:data,ss:stack
zz1   proc far
start:mov ax,data
      mov ds,ax
      mov es,ax
      lea si,s1
      mov cx,count   ;**
      mov ax,si
      add ax,cx
      mov di,ax
      mov al,11
      mov dl,1
l1:   mov bx,si
      add bx,di
      shr bx,1
      cmp al,[bx]
      je j1
      pushf
      cmp bx,si
      je j2
      popf
      jl j3
      mov si,bx
      jmp j4
j3:   mov di,bx
j4:   inc dl
      jmp l1
j2:   mov dl,0ffh
j1:   mov s2,dl
      ret
zz1   endp
code  ends
      end start