有道题目：从键盘输入一系列以$为结束符的字符串，然后对其中的非数字字符计数，并显示出计数结果。
以下为小弟的程序：
STACK SEGMENT
DB 200(?)
STACK ENDS
DATA SEGMENT
SUM DB ?
BUF DB "PLASE INPUT A CHARACTER STRING:$ "
BUF1 DB 30
DB ?
DB 30 DUP(?)
BUF2 DB 0AH,0DH, "(SUM)= "
BUF3 DB 4 DUP(?)
DATA ENDS
CODE SEGMENT
ASSUME DS:DATA,CS:CODE,SS:STACK
BEGIN:MOV AX,DATA
MOV DS,AX
MOV AH,9
LEA DX,BUF
INT 21H
MOV AH,10
LEA DX,BUF1
INT 21H
XOR CL,CL
LEA SI,BUF1+2
COMP:MOV DL,[SI]
CMP DL, "$ "
JZ DISPLAY
CMP DL,30H
JB CHAR
CMP DL,39H
JA CHAR
INC SI
JMP COMP
CHAR:INC SI
INC CL
JMP COMP
DISPLAY:MOV SUM,CL
LEA DI,BUF3
MOV SUM,AL
MOV CL,4
SHR AL,CL
OR AL,30H
MOV BUF3,AL
INC DI
AND AL,0FH
OR AL,30H
CMP AL,3AH
JB STORE
ADD AL,07H
STORE:AND AL,0FH
MOV BUF3,AL
INC DI
MOV BYTE PTR[DI], 'H '
INC DI
MOV BYTE PTR[DI], '$ '
MOV AH,9
LEA DX,BUF2+4
INT 21H
MOV AH,4CH
INT 21H
CODE ENDS
END BEGIN