Riddler 2018-08-31 Express, "The New National Pastime: Competitive Coin Flipping"

2018-08-31-express.py

import random

def enum(**enums):
    return type('Enum', (), enums)

Coin = enum(HEADS='H', TAILS='T')
Team = enum(RED='Red', BLUE='Blue')
Goal = enum(RED=[Coin.HEADS, Coin.TAILS], BLUE=[Coin.HEADS, Coin.HEADS])

def flip():
	return random.choice([Coin.HEADS, Coin.TAILS])

def play():
	winner = None
	sequence_red = []
	sequence_blue = []
	while(winner is None):
		sequence_red.append(flip())
		sequence_blue.append(flip())
		if (len(sequence_red) >= 2):
			if (sequence_red[-2:] == Goal.RED):
				winner = Team.RED
			if (sequence_blue[-2:] == Goal.BLUE):
				if winner is Team.RED:
					winner = None
					sequence_red = []
					sequence_blue = []
				else:
					winner = Team.BLUE
	return winner

def simulate(trials=100):
	results = {Team.RED:0, Team.BLUE:0}
	p = 0
	for i in xrange(1, trials+1):
		results[play()] += 1
		if (i%(10**p) == 0):
			print {k:(v*1.0/sum(results.values())) for k,v in results.iteritems()}
			p += 1
	return results

print simulate(10000000)
"""
Output:
{'Blue': 0.0, 'Red': 1.0}
{'Blue': 0.4, 'Red': 0.6}
{'Blue': 0.36, 'Red': 0.64}
{'Blue': 0.353, 'Red': 0.647}
{'Blue': 0.3672, 'Red': 0.6328}
{'Blue': 0.37538, 'Red': 0.62462}
{'Blue': 0.376188, 'Red': 0.623812}
{'Blue': 0.3752312, 'Red': 0.6247688}
{'Blue': 3752312, 'Red': 6247688}
"""