阅读下面的程序，回答问题

DATA SEGMENT

BUF DB '1234'

N=$-BUF

BCD DB N DUP(?)

DATA ENDS

CODE SEGMENT

ASSUME CS:CODE,DS:DATA

START：MOV AX,DATA

MOV DS,AX

LEA SI,BUF

MOV CX,N

LEA DI,BCD+N-1

LOOP1：MOV AL,[SI]

SUB AL,30H

MOV [DI],AL

INC SI

DEC DI

DEC CX

JNE LOOP1

MOV AH,4CH

INT 21H

CODE ENDS

END START

画出内存分配图。