The Monty Hall Problem

cars_behind_doors.py

from random import randint

def change_mind(i_chose, host_opened):
    if i_chose == 1 and host_opened == 2:
        return 3
    if i_chose == 1 and host_opened == 3:
        return 2
    if i_chose == 2 and host_opened == 1:
        return 3
    if i_chose == 2 and host_opened == 3:
        return 1
    if i_chose == 3 and host_opened == 1:
        return 2
    if i_chose == 3 and host_opened == 2:
        return 1

def one_round(changed_mind):
    car_behind_door = randint(1, 3)
    i_choose = randint(1, 3)
    host_opens = randint(1, 3)
    while host_opens == car_behind_door or host_opens == i_choose:
        host_opens = randint(1, 3)
    print(f"Car is behind door {car_behind_door}. I choose door {i_choose}. The host opens {host_opens}.")
    if changed_mind:
        i_choose = change_mind(i_choose, host_opens)
        print(f"I change my mind and choose {i_choose} instead")
    else:
        print("I stick with my original guess")
    win =  i_choose == car_behind_door
    print("WIN!" if win else "lose")
    return win

wins = 0
for n in range(0, 1000):
    if one_round(True):
        wins += 1
print(f"{wins} total wins")