#! /usr/bin/env stack
-- stack --resolver lts-12.20 --install-ghc script
{-# LANGUAGE DeriveFunctor, DeriveFoldable #-}
module Main where

import qualified Control.Monad.State as St
import qualified Data.List           as L
import qualified Data.Monoid         as Mo

data Node a = Node [Node a] a deriving (Show, Functor, Foldable)

main :: IO ()
main = interact $ show . Mo.getSum . foldMap (foldMap Mo.Sum) . parseTree

parseTree :: String -> Node [Int]
parseTree = St.evalState parseNode

parseNode :: St.State String (Node [Int])
parseNode = do
   nChildren <- parseInt
   nMetadata <- parseInt
   Node <$> St.replicateM nChildren parseNode
        <*> St.replicateM nMetadata parseInt

parseInt :: St.State String Int
parseInt = read <$> St.state (L.break (== ' ') . L.dropWhile (== ' '))