怎么使相同的数据不显示

如何使相同的数据不显示
a1输入1,2,3,12,23,33,1,3,15,16,17,16,23,2,17
b1得出的结果为:1,2,3,12,15,16,17,23,33
请教一下b1公式应怎么写!!

[解决办法]
在VBA中：

VB code

Option ExplicitSub f()    Dim s() As String    Dim ret As String    Dim i As Integer    Dim j As Integer    s = Split(Sheet1.Cells(1, 1), ",")    For i = 0 To UBound(s)        Dim f As Boolean        f = True        If InStr(1, ret, s(i) & ",") > 0 Then            f = False        End If        If f Then            ret = ret & s(i) & ","        End If    Next    If Right(ret, 1) = "," Then       ret = Mid(ret, 1, Len(ret) - 1)    End If    Sheet1.Cells(2, 1) = retEnd Sub
[解决办法]
VB code
Sub test()    Dim d As Object, temp, i&, k&    For k = 1 To ActiveSheet.UsedRange.Rows.Count        temp = Split(Cells(k, 1).Value, ",")        Set d = CreateObject("scripting.dictionary")        For i = 0 To UBound(temp)            d(temp(i) & "") = ""        Next        Cells(k, 2) = Join(d.keys, ",")        d.RemoveAll    Next    Set d = NothingEnd Sub