10.11.ml

#use "metro.ml"

(* 目的:ふたつの駅の漢字の駅名とリストを受け取って2駅間の距離を返す *)
(* get_ekikan_kyori : string -> string -> ekikan_t list -> float *)
let rec get_ekikan_kyori s1 s2 lst =
  if s1 = s2
  then 0.
  else match lst with
	 [] -> infinity
       | first::rest -> if (first.kiten = s1 && first.shuten = s2) ||
			     (first.kiten = s2 && first.shuten = s1)
			then first.kyori
			else get_ekikan_kyori s1 s2 rest
					      
(* テスト *)
let test1 = get_ekikan_kyori "茗荷谷" "茗荷谷" global_ekikan_list = 0.
let test1 = get_ekikan_kyori "茗荷谷" "新大塚" global_ekikan_list = 1.2
let test2 = get_ekikan_kyori "新大塚" "茗荷谷" global_ekikan_list = 1.2
let test3 = get_ekikan_kyori "北千住" "茗荷谷" global_ekikan_list = infinity