QuickMacro - find duplicate array members

Dim a={1,2,3,1,1}
For i = 0 To UBound(a) - 1
    For j = i + 1 To UBound(a)
        If a(i) = a(j) Then
            TracePrint "a(" & i & ") 和 a(" & j & ") 重复。"
            Exit for
        End If
    Next
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