include IO.ASM
  d segment
 	B db 'Error! You entered more than 100 symbols! You must enter again and it must be less$'
	q db 'text is empty$'
        X db 101 dup (?)
 	Src db 'Old text: $'
 	Ru db 'Rule: $'
 	New db 'New text: $'
  d ends
  s segment stack
        db 128 dup (?)
  s ends
  c segment
        assume cs: c, ds: d, ss: s
 start: mov ax, data
        mov ds, ax
;Ââîä òåêñòà
Re:     outch '>'
 	mov cx, 1
 	sub si, si
Next:   inch X[si]
	cmp X[si], '.'
 	je EI
 	cmp cx, 64h
 	jae Ls
	inc cx
 	inc si
 	jmp Next
Ls:     lea dx, B
 	outstr
 	flush
 	newline
 	jmp Re 
EI:     dec cx
	cmp si,0
	jne EIp
	lea dx, q
 	outstr
 	flush
 	newline
 	jmp Re 
EIp:	mov X[si], '$'
        lea dx, Src
 	outstr
 	lea dx, x
 	outstr
 	newline
	lea ax, x
 	push ax
 	call Prove
 	lea dx, Ru
 	outstr
 	outint ax
 	newline
	cmp ax, 1
 	jne LR2
 	lea ax, x
 	push ax
	call Rule1
 	jmp End4
LR2:    lea ax, x
 	push ax
	push cx
 	call Rule2
End4:   lea dx, New
 	outstr
 	lea dx, x
 	outstr
 	newline
finish

;Function checks the property
;ax=1 - true. ax=2 - false

Prove proc  
 	push bp
 	mov bp, sp
 	push bx
 	push si
 	sub si, si
 	mov bx, [bp+4]
CD: cmp [bx][si], byte ptr '0'       
 	jb N
 	cmp [bx][si], byte ptr '9'
 	ja p1
p1:	cmp [bx][si], byte ptr 'A'       
 	jb N
 	cmp [bx][si], byte ptr 'Z'
 	ja p2
p2:	cmp [bx][si], byte ptr 'a'       
 	jb N
 	cmp [bx][si], byte ptr 'z'
 	ja N
        inc si
 	cmp byte ptr [bx][si], '$'
 	jne CD
 	mov ax, 1
 	jmp E1
N:      mov ax, 2
	jmp E1
E1:     pop si
 	pop bx
 	pop bp
 	ret 4
Prove endp

Rule1 proc  
 	push bp
 	mov bp, sp
 	push bx
 	push si
 	push cx
 	sub si, si
 	mov bx, [bp+4]
Next2:  cmp [bx][si], byte ptr 'a'       
 	jb N2
 	cmp [bx][si], byte ptr 'z'
 	ja N2
 	mov cx, 'a'
 	sub [bx][si], cx
 	mov cx, 'A'
 	add [bx][si], cx
N2:    inc si
 	cmp [bx][si], '$'
 	jne Next2
 	pop cx
 	pop si
 	pop bx
 	pop bp
 	ret 4
Rule1 endp 
 
Rule2 proc 
 	push bp
 	mov bp, sp
 	push bx
 	push si
 	push cx
 	push ax
	push dx
	push di
 	mov di, [bp+4]
 	mov bx, [bp+6]
	mov di,ax
	xor dx,dx
	mov cx,2
	div cx
	add ax,dx
	dec ax
	mov cx,ax
Next3:  mov si,cx
	mov dx,di
	sub di,si
	xchg byte ptr [bx][si],[bx][di]
	mov di,dx
	loop Next3
	pop di
	pop dx
	pop ax
 	pop cx
 	pop si
 	pop bx
 	pop bp
 	ret 6
Rule2 endp
   c ends
        end start