CODE
.MODEL SMALL[code]
.STACK 100h
.DATA
MAXIMUM_STRING_LENGTH EQU 1000
StringToReverse DB 'Type a string: $';MAXIMUM_STRING_LENGTH DUP(?)
ReverseString DB 13,10,'Result: $';MAXIMUM_STRING_LENGTH DUP(?)
.CODE
mov ax,@data
mov ds,ax ;set DS to point to the data segment
mov ah,3fh ;DOS read from handle function #
mov bx,0 ;standard input handle
mov dx,OFFSET StringToReverse ;store the string here
mov cx,MAXIMUM_STRING_LENGTH ;read up to maximum number of characters
int 21h ;get the string
and ax,ax ;were any characters read?
jz Done ;no, so you're done
mov cx,ax ;put string length in CX, where
; you can use it as a counter
push cx ;save the string length
mov bx,OFFSET StringToReverse
mov si,OFFSET ReverseString
add si,cx
dec si ;point to the end of the
; reverse string buffer
ReverseLoop:
mov al,[bx] ;get the next character
mov [si],al ;store the characters in reverse order
inc bx ;point to next character
dec si ;point to previous location in reverse buffer
loop ReverseLoop ;move next character, if any
pop cx ;get back the string length
mov ah,40h ;DOS write from handle function #
mov bx,1 ;standard output handle
mov dx,OFFSET ReverseString ;print this string
int 21h ;print the reversed string
Done:
mov ah,4ch ;DOS terminate program function #
int 21h ;terminate the program
END
why was i dont have any ouput when I run or compile this program yet when i chck it, it has no errors?
the program should reverse an inputted string
This post has been edited by reign: 4 Oct, 2008 - 07:42 PM
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