#!/usr/bin/env python

import MersenneTwister19937

import random, string

class KingCoin:
    def __init__(self):
        seed = random.randint(0, 2**60)
        self.mt = MersenneTwister19937.MersenneTwister19937(seed)

        self.FOUR_DIFFERENT	= 3	# 4 different colors in 4 spins 
        self.SIX_SPINS		= 2.5	# 6 spins, any color
        self.THREE_IN_ROW	= 2	# 3 in a row 
        self.THREE_OF_FIVE	= 1.5	# 3 out of 5 (needs 5 non-black spins to pay)
        self.LOSE		= 0	# spinning black = lose

    def play_once(self):
        wheel = '1'*3 + '0'*450
        wheel = [150] + map(lambda x: len(x)+100, string.split(self.mt.shuffle_string(wheel), '1'))
        n = 0
        spots = []
        for c in wheel:
            spots += c*[n]
            if (n == 0):
                n += 1
            else:
                n *= 2

        self.spots = self.mt.shuffle(spots)[:6]
        s0, s1, s2, s3, s4, s5 = self.spots

        # 3 spins
        if s0==0 or s1==0 or s2==0:	return self.LOSE
        if s0==s1 and s1==s2:		return self.THREE_IN_ROW

        # 4 spins
        if s3==0:			return self.LOSE
        if s0+s1+s2+s3 == 15:		return self.FOUR_DIFFERENT
        if s1==s2 and s2==s3:		return self.THREE_IN_ROW

        # 5 spins
        if s4==0:			return self.LOSE
        if s1+s2+s3+s4 == 15:		return self.FOUR_DIFFERENT
        if s2==s3 and s3==s4:		return self.THREE_IN_ROW
        c = {}
        for i in self.spots[0:5]:
            if c.has_key(i):
                c[i] += 1
                if c[i] == 3:		return self.THREE_OF_FIVE
            else:
                c[i] = 1

        # 6 spins
        if s5==0:			return self.LOSE
        if s2+s3+s4+s5 == 15:		return self.FOUR_DIFFERENT
        else:				return self.SIX_SPINS

k = KingCoin()

spins = 100000
sum = 0.0
for i in range(spins):
    sum += k.play_once()

print "average return over %d spins is %f" % (spins, sum / spins)

>>> 1 - 64000/65536.0
0.0234375

>>> (1 - 64000/65536.0)**3
1.2874603271484375e-05