Monty Hall Simulator

from random import randint, random, choice

class MontyHallDoors():
    def __init__(self):
        self.doors = [0 for i in range(3)]
        self.car_door = randint(0,2)
        self.doors[self.car_door] = 1

    def is_car_door(self,i):
        return self.doors[i] == 1

    def get_car_door(self):
        return self.car_door

    def __str__(self):
        l = []
        for i in range(3):
            if self.is_car_door(i):
                l.append("car")
            else:
                l.append("goat")
        return "[{}, {}, {}]".format(l[0],l[1],l[2])

stay_attempts = []
switch_attempts = []

for i in range(100000):
    monty = MontyHallDoors()

    car_door = monty.get_car_door()

    # pick first door for the contestant
    first_door = randint(0,2)

    # offer the switch
    if(first_door == car_door):
        open_door = choice([i for i in range(3) if i != first_door])
    else:
        open_door = 3 - first_door - car_door

    offered_door = 3 - first_door - open_door

    # pick your strategy: stay or switch
    stay_mode = random() <= 0.5

    # do the switch if decided to
    chosen_door = offered_door if not stay_mode else first_door

    # check if door is correct and append to the correct strat
    if(stay_mode):
        stay_attempts.append(car_door == chosen_door)
    else:
        switch_attempts.append(car_door == chosen_door)

    #print(monty)
    #print("Mode: {}".format("stay" if stay_mode else "switch"))
    #print("first door: {}".format(first_door))
    #print("final door: {}".format(chosen_door))
    #print("Result: {}".format("Win" if car_door == chosen_door else "lose"))

stay_winning_chance = 1.0*len([0 for i in range(len(stay_attempts)) if stay_attempts[i]])/len(stay_attempts)

switch_winning_chance = 1.0*len([0 for i in range(len(switch_attempts)) if switch_attempts[i]])/len(switch_attempts)

print(stay_winning_chance, switch_winning_chance)