Програма для нахождения разных цифр числа

Dim a As String, i As Integer, j As Integer
 
Private Sub Form_Load()
a = InputBox("ââåäèòå ÷èñëî")
For i = 1 To Len(a)
    For j = i + 1 To Len(a)
        If Mid$(a, i, 1) = Mid$(a, j, 1) Then
        MsgBox "â ÷èñëå  " & a & "  åñòü ïîâòîðÿþùèåñÿ öèôðû"
        Exit Sub
        End If
    Next j
Next i
MsgBox "â ÷èñëå  " & a & "  íåò ïîâòîðÿþùèõñÿ öèôð"
End Sub

Function isDiffDig(n as long) as Boolean
Dim Z(0 to 9) As integer
     S$=Cstr(n)
     For i%=1 to len(S$)
          a%=Val(Mid$(S$,i%,1))
          if Z(a%)<> 0 then
            isDiffDig=False
            Exit Function
          End if
     Next i%
     isDiffDig=True
End Function

Function isDiffDig(n as long) as Boolean
Dim Z(0 to 9) As integer
     S$=Cstr(n)
     For i%=1 to len(S$)
          a%=Val(Mid$(S$,i%,1))
          if Z(a%)<> 0 then
            isDiffDig=False
            Exit Function
          End if
          Z(a%)=Z(a%)+1 '!!!!!! пропустил - увлекся.
     Next i%
     isDiffDig=True
End Function

Function isDiffDig(ByVal n As Long) As Boolean
Dim Z(0 To 9) As Boolean
While n
  If Z(n Mod 10) Then Exit Function Else Z(n Mod 10) = True: n = n \ 10
Wend
isDiffDig = True
End Function

Private Sub Command1_Click()
Print r(1, CStr(125784), "")
End Sub
Function r(k, b$, s$) As Boolean
   If InStr(1, s, Mid(b, k, 1)) = 0 And k <= Len(b) Then
      s = s + Mid(b, k, 1)
      r k + 1, b, s
   End If
 r = (Len(s) <> Len(b))
End Function

Option Explicit
 
Private Sub Form_Load()
    Debug.Print isDiffDig(1238743)
End Sub
Function isDiffDig(n As Variant, Optional q As Long) As Boolean
    q = Len(CStr(n)) - 1: n = Replace(CStr(n), Left$(CStr(n), 1), vbNullString)
    If Len(n) = q Then If Len(n) Then isDiffDig = isDiffDig(n) Else isDiffDig = True Else Exit Function
End Function

Function isDiffDig(n as long) as Boolean
     Z%=0
     S$=Cstr(n)
     For i%=1 to len(S$)
          a%=2^Val(Mid$(S$,i%,1))
          If (Z% AND a%) <> 0 then
            isDiffDig=False
            Exit Function
          End if
          Z=Z OR a%
     Next i%
     isDiffDig=True
End Function