fighter.py

import shlex

from game import MultiplayerAvocado
from subprocess import Popen, PIPE

MOVES = {
    0: 'slice',
    1: 'mash',
    2: 'eat',
    3: 'buy'
}


def fight(a, b):
    a = shlex.split(a)
    b = shlex.split(b)
    game = MultiplayerAvocado()
    while True:
        if game.turn == 0: turn = a
        else: turn = b
        print(turn + [game.spoon] + game.previous)
        proc = Popen(turn + [str(game.spoon)] + list(map(str, game.previous)), stdout=PIPE, stderr=PIPE)
        out, err = proc.communicate()
        if err:
            break

        print(out)
        try:
            out = int(out)
            if len(game.previous) == 0:
                game.set_avocados(out)
            elif game.spoon == -1:
                game.set_spoon(out)
            else:
                game.__getattribute__(MOVES[out])()
        except (ValueError, KeyError):
            break

    return (game.turn + 1) % 2

game.py

class MultiplayerAvocado:

    def __init__(self):
        self.spoon = -1
        self.turn = 0
        self.previous = []

    def switch_turn(self):
        if self.previous[-1] in self.previous[:-1] or self.previous[-1] < 0:
            raise ValueError
        else:
            self.turn = (self.turn+1) % 2

    def set_avocados(self, count):
        if count < 0: raise ValueError
        self.previous.append(count % 256)
        self.switch_turn()

    def set_spoon(self, count):
        if count < 1: raise ValueError
        self.spoon = count % 256
        self.switch_turn()

    def slice(self):
        for x in reversed(range(2, self.avocados/2 + 2)):
            if x % self.avocados == 0:
                if x in [0, 1, self.avocados]:
                    raise ValueError
                self.previous.append(x)
        
        self.switch_turn()

    def mash(self):
        avocados = self.previous[-1] ** 2
        avocados %= 2 ** 8
        self.previous.append(avocados)
        self.switch_turn()

    def eat(self):
        self.previous.append(self.previous[-1] - self.spoon)
        self.switch_turn()

    def buy(self):
        avocados = self.previous[-1] + self.spoon
        avocados %= 2 ** 8
        self.previous.append(avocados)
        self.switch_turn()