; PROGRAMMED BY   : MOHAMMAD ALJADA
; DOWNLOADED FROM : WWW.GEOCITIES.COM/MOHJADA
; PROGRAM         : SUB Numbers

.model small
.stack 64
.data
a db 'a=','$'
b db 0ah,0dh,'b=','$'
r db 0ah,0dh,'Sub of ab='
rr db '+'
t db ?,'$'
.code
main proc far
mov ax,@data
mov ds,ax

mov ah,09       ;display
lea dx,a        ;text to display
int 21h

mov ah,01       ;input
int 21h

mov t,al
mov ah,09
lea dx,b
int 21h


mov ah,01
int 21h


neg al
add t,al
mov bl,t
mov t,bl


jns l1
mov rr,'-'
neg t

l1:
add t,30h

mov ah,09
lea dx,r
int 21h

mov ah,4ch
int 21h
main endp
end main