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module Main where

import Control.Monad
--import Data.Monoid

data State s a = State (s -> (a, s))

runState :: State s a -> s -> (a, s)
runState (State f) = f

instance Monad (State s) where
			return a = State $ \s -> (a, s)
			ma >>= mf = State $ \s0 -> let (b, s1) = runState ma s0 
				in runState (mf b) s1

type FSM s = State s s 

fsm :: (ev -> s -> s) -> (ev -> FSM s)
fsm transition = \e -> State $ \s -> (s, transition e s)

data PN = NONZ | PONZ | POPZ | NOPZ deriving (Eq,Show)

parse :: Int -> FSM PN
parse = fsm $ trans 
	where trans 1 NONZ= PONZ
	      trans 1 NOPZ= POPZ
	      trans 1 POPZ= NOPZ
	      trans 1 PONZ= NONZ
	      trans 0 POPZ= PONZ
	      trans 0 PONZ= POPZ
	      trans 0 NONZ= NOPZ
	      trans 0 NOPZ= NONZ
	      
conv [] = []
conv ('1':xs) = 1:(conv xs)
conv ('0':xs) = 0:(conv xs)
conv (_:xs) = error "parse error"

main =do
	x <- getLine
	print $ (snd $ runState (mapM parse (conv x)) POPZ) == POPZ
	print $ runState (mapM parse (conv x)) POPZ