28.asm

字符串逆序,这是第一次来上传东西,希望大家给个介意.

data segment
string1 DB "please input a string:$"
BUF   DB 254
      DB ?
      DB 254 DUP (?)
count  equ $-string1
string2 db count dup(?),'$'
CRLF  DB 0AH,0DH,"$"
data ends
code segment
assume cs:code,ds:data
start:mov ax,data
      mov ds,ax
      LEA DX,string1
       MOV AH,9
       INT 21H
       MOV AH,10
       LEA DX,BUF
       INT 21H
       LEA DX,CRLF
       MOV AH,9
       INT 21H
      mov cx,count
      mov si,offset string1
      add si,cx
      dec si
      mov di,offset string2
lop1: mov al,[si]
      mov [di],al
      dec si
      inc di
loop  lop1
mov dx,offset string2
mov ah,9
int 21h
mov ah,4ch
int 21h
code ends
end start