Private Sub Worksheet_Change(ByVal Target As Range)
Dim L As Long, C As Long
If Target.Address = "$C$10" Then
L = WorksheetFunction.Match(Me.[C8].Value, Feuil2.[B6:B10], 0)
C = WorksheetFunction.Match(Me.[C6].Value, Feuil2.[C5:N5], 0)
With Feuil2.[C6:N10].Cells(L, C)
If Me.[C12].Value Then .Value = .Value + Target.Value Else .Value = Target.Value
End With
End If
End Sub