-module(nesting).
-export([nesting/1]).

nesting(S) ->
    case close_stack(S, []) of
        [] -> 1;
        _  -> 0
    end.

close_stack([], Stack) -> Stack;
close_stack([$) | T], [$( | Rest]) -> close_stack(T, Rest);
close_stack([$) | _], _Stack) -> error;
close_stack([C | T], Stack) -> close_stack(T, [C | Stack]).