Sub doublon()
'tRes est le tableau résultat
Dim tSource, tRes, dico, i&, n&, k&, clef
tSource = Sheets("Feuil1").Range("a1:b" & Sheets("Feuil1").Cells(Rows.Count, "a").End(xlUp).Row)
Set dico = CreateObject("Scripting.Dictionary")
For i = 2 To UBound(tSource): dico(tSource(i, 1) & tSource(i, 2)) = i: Next i
ReDim tRes(1 To dico.Count, 1 To 2)
For Each clef In dico
n = n + 1: k = dico(clef)
tRes(n, 1) = tSource(k, 1): tRes(n, 2) = tSource(k, 2)
Next clef
End Sub