实验一流程图：
实验一代码：
SSTACK SEGMENT STACK
DW 64 DUP(?)
SSTACK ENDS
DATA1 SEGMENT
MES1 DB '1_SAVE 2_COST 3_CHECK 4_EXIT','$'
MES2 DB 'SUCCES','$'
MES3 DB 'NOT_ENOUGH','$'
MES4 DB 'YOUR ACCOUNT:','$'
MES5 DB 'HOW MUCH:','$'
DATA1 ENDS
CODE SEGMENT
ASSUME CS:CODE
START:
MOV BL,30H
MOV AX,DATA1
MOV DS,AX
MOV DX,OFFSET MES4
MOV AH,09H
INT 21H
MOV DL,30H
MOV AH,02H
