e6_62.asm

ZHUYAO ZSHI LAI JIECHUADE LAIDE

stack segment stack
      db 256 dup(?)
stack ends
code segment
     assume cs:code,ss:stack
star:push cs
     pop ds
     mov ax,x
     or  ax,ax
     je  zero
     jns plus
     mov bl,0ffh
     jmp exit
zero:mov bl,0
     jmp exit
plus:mov bl,1
exit:mov y,bl
     mov ah,4ch
     int 21h
  x  dw 300h
  y  db ?
code ends
     end star