import random

class Game(object):
    def __init__(self):
        self.pile = -1
        self.computerWins = 0
        self.userWins = 0
    def start(self):
        self.userWins = 0
        self.computerWins = 0
        while True:
            self.pile = int(raw_input("Size: "))
            while True:
                if self.userMove() != "go on":
                    break
                if self.computerMove() != "go on":
                    break
            print "The score is", (self.userWins, self.computerWins)
            if raw_input("Play again?") == "no":
                break            
    def userMove(self):
        user = int(raw_input("Your turn: "))
        self.pile = self.pile - user
        if self.pile < 0:
            print "You lost."
            self.computerWins = self.computerWins + 1
            return "end the game"
        print "The pile becomes", self.pile, "computer moves now"
        return "go on"

    def computerMove(self):
        computer = random.randrange(10)
        print "Computer withdraws", computer
        self.pile = self.pile - computer
        if self.pile < 0:
            print "The computer lost."
            self.userWins = self.userWins + 1
            return "end the game"
        print "The pile becomes", self.pile, "it's your turn now"
        return "go on"