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在 MASM 程序集中，如果用户写“-22”，我想检查第一个字符是否有“-”符号，然后删除它。如果用户写“+12”，我想检查第一个字符是否有“+”号，然后删除它。

下面的代码不起作用。有人可以让我知道代码有什么问题。

insertNums:

    lodsb

    cmp     ch, 43  ;I am not sure if this is the proper way of checking for a "+"
    je      convertPos
    cmp     ch, 45  ;Same with this. Does this check for ASCII 45 which is "-"?
    je      convertNeg
continue:
    cmp     eax, 0
    je      endInsert
    sub     eax, 48
    mov     ebx, eax
    mov     eax, value
    mov     edx, 10 ;multiplies by 10
    imul    edx
    jc      tooLargeNumber ; check for carry after multiply
    add     eax, ebx ;add the digit to the converted value
    jc      tooLargeNumber ; check for carry after adding
    mov     value, eax ; store temporary value from eax
    mov     eax, 0 ; reset eax
    loop    insertNums
    jmp     endInsert


convertPos:
; this is for positive numbers
; the goal is to just drop the'+' sign and feed it back to the loop

convertNeg:
; this one is supposed to drop the '-' sign
; and once I know it is a negative number, I would have a separate procedure for ;converting the number to a negative
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