type wertpapier = { bez : string; wert : int }

type kunde = { name : string; portfolio : (int * wertpapier) list }

(* drei moegliche Loesungen fuer Teil c) *)

let rec portfoliowert portfolio =
  match portfolio with 
      [] -> 0
    | (a,w)::ws -> a * w.wert + portfoliowert ws

let rec portfoliowert = function
    [] -> 0
  | (a,w)::ws -> a * w.wert + portfoliowert ws

let rec portfoliowert = List.fold_left (fun s (a,w) -> s + a * w.wert) 0

let kundenwert k = portfoliowert k.portfolio

let rec anzahl praedikat kunden_liste =
  match kunden_liste with
      [] -> 0
	| k::ks -> 
	    anzahl praedikat ks +
		if praedikat k then
		  1
		else
	      0

(* drei moegliche Loesungen fuer Teil f) *)

let rec filter praedikat kunden_liste = 
  match kunden_liste with
      [] -> []
	| k::ks -> 
		if praedikat k then
		   k::filter praedikat ks
		else
		   filter praedikat ks

let filter praedikat kunden_liste = List.filter praedikat kunden_liste

let filter = List.filter

let grosskunden = filter (fun k -> kundenwert k >= 1000000)