;; open Assert

type tree = 
	| Empty 
	| Node of tree * int * tree

let t : tree = Node ( Node (Empty , 2 , Empty ) , 1 ,
	                    Node (Empty , 3 , Empty ) ) 
											
let rec size ( t : tree ) : int = 
		begin match t with
			| Empty -> 0
			| Node ( l , v , r ) -> 1 + size l + size r 
		end			
		
let test () : bool = size t = 3
;; run_test "size t" test