dosseg
.model small
.data

jjj db 'Enter 0 or 1 $'
.stack 100h
.code

main proc


mov ax, @data
mov ds, ax
lea dx, jjj

mov ah, 9
int 21h

mov ah, 1
int 21h

mov bl, al
cmp bl, 48
je smol
jne capital

smol:

mov cx, 26
mov dx, 97
mov bx, 97

L1:
mov dx, bx
mov ah, 2
int 21h
add dx, 1
mov bx, dx

Loop L1

jmp common

capital:

mov cx, 26
mov dx, 65
mov bx, 65

L2:
mov dx, bx
mov ah, 2
int 21h
add dx, 1
mov bx, dx

Loop L2

common:

mov ah, 4ch
int 21h

main endp
end main