Option Explicit

Private Const szKeyNumber As String = "0123456789ABCDEFGHJKLMNPQRSTUVWXYZ"
Private Const nKeyLen As Long = 34

Private Function Digits(s As String) As Boolean
    Dim b As Boolean, i As Long, c As String
    b = True
    For i = 1 To Len(s)
        c = Mid(s, i, 1)
        If InStr(szKeyNumber, c) = 0 Then
            b = False
            Exit For
        End If
    Next
    Digits = b
End Function

Private Function GetKeyValue(Key As String) As Long
    Dim n As Long, i As Long, p As Long
    Dim d As Long
    d = nKeyLen
    n = 0
    For i = 1 To Len(Key)
        p = InStr(szKeyNumber, Mid$(Key, i, 1)) - 1
        n = n * d + p
    Next i
    GetKeyValue = n
End Function

Private Function MirrorLong(ByVal n As Long) As Long
    Dim p As Long, i As Long
    p = 0
    For i = 1 To 30
        p = p * 2 + (n And 1)
        n = n \ 2
    Next i
    MirrorLong = p
End Function

Public Function CheckKey(Key As String, Prefix As String, id As Long) As Long
    Dim s As String, s1 As String, s2 As String, s3 As String
    Dim b As Boolean, v1 As Long, v2 As Long
    Dim n As Long, nn As Double
    b = False
    s = UCase$(Trim$(Key))
    n = Len(Prefix)
    If Len(s) = 15 + n And Left$(s, n + 1) = Prefix & "-" And Mid$(s, 6 + n, 1) = "-" And Mid$(s, 11 + n, 1) = "-" Then
        s1 = Mid$(s, 2 + n, 4)
        s2 = Mid(s, 7 + n, 4)
        s3 = Mid(s, 12 + n)
        If Digits(s1) And Digits(s2) And Digits(s3) Then
            v1 = MirrorLong(GetKeyValue(s1 & Left$(s2, 2)))
            v2 = MirrorLong(GetKeyValue(s3 & Mid$(s2, 3)))
            n = nKeyLen * nKeyLen * nKeyLen
            n = n * n
            v1 = v1 And &H1FFFFFFF
            v2 = ((Not v2) And &H1FFFFFFF) Mod n
            b = (v1 = v2)
            v2 = v1 \ &H100000
            If b And v2 <> id Then b = False Else v1 = v1 And &HFFFFF
        End If
    End If
    CheckKey = IIf(b, v1, -1)
End Function

[招生]科锐逆向工程师培训(2024年11月15日实地，远程教学同时开班, 第51期)