let id = fun x -> x;;

let check_item_against_item = fun pin1 pin2 ->
    true (*( List.fold_left2 ( fun prev i1 i2 -> i1 * i2 + prev ) 0 pin1 pin2 ) == 1*)
;;

let rec check_list_against_item = fun pins pin -> match pins with
    | [ ] -> true
    | head :: tail -> check_item_against_item head pin && check_list_against_item tail pin
;;

let rec check_set = fun pins -> match pins with
    | [ ] -> true
    | head :: tail -> check_list_against_item tail head && check_set tail tail
;;

let rec make_list = fun n f -> match n with
    | 0 -> [ ]
    | _ -> [ f( ) ] @ make_list (n-1) f
;;

let _ =
    let n = Scanf.scanf "%d " id in
    let m = Scanf.scanf "%d " id in
    let pins = make_list n (fun _ ->
        make_list m (fun _ ->
            Scanf.scanf "%c" ( function
                'o' -> 1
                | _ -> 0
            )
        )
    ) in
    check_set pins
;;