sub changecouleur()
dim coul as byte
coul = 4
For Each c In Range('b1:b' & Range('b65536').End(xlUp).Row)
If c.Row = 1 Then
c.Interior.ColorIndex = coul
ElseIf c = c.Offset(-1, 0) Then
c.Interior.ColorIndex = coul
ElseIf c <> c.Offset(-1, 0) Then
If coul = 4 Then
coul = 3
Else
coul = 4
End If
c.Interior.ColorIndex = coul
End If
Next c
end sub