Excel: somme valeurs avec conditions

Option Explicit

Const lideb = 2   ' premièere ligne 0
Const codeb = 1   ' colonne 0-15
Const cores = 5   ' colonne résultat

Public Sub ok()
Dim li1 As Long, li2 As Long, lifin As Long, s
Application.ScreenUpdating = False
lifin = Cells(Rows.Count, codeb).End(xlUp).Row
li1 = lideb
While Cells(li1 + 1, codeb) = 0
  li1 = li1 + 1
Wend
li2 = li1
While li2 < lifin
  s = 0
  Do
    s = s + Cells(li2, codeb + 1)
    li2 = li2 + 1
  Loop Until Cells(li2, codeb) = 0 Or Cells(li2, codeb) = ""
  If s <> 0 Then Cells(li1, cores) = s
  li1 = li2
Wend
End Sub