let rec usun_po_15_30 (list:Wydarzenie list) =
    match list with
    | [] -> []
    | x :: xs ->
        if x.Godzina.Godzina*60+x.Godzina.Minuta >= 15*60+30 then
            usun_po_15_30 xs
        else
            x::xs
usun_po_15_30 lista_wyd