In [1]:

    

from __future__ import division
from tqdm import *
import numpy as np 
import scipy.stats as st


    

In [2]:

    

def round(index):
    
    i = 0
      
    odd_previous_heads = False
    
    while(True):
        # 0 = heads, 1=tails
        elem = np.random.choice([0,1])
        i += 1
        
        if(elem == 0):
            if(odd_previous_heads == True):
                odd_previous_heads = False
            else:
                odd_previous_heads = True
                
        else:
            if(odd_previous_heads == True):
                return i
            else:
                continue


    

In [3]:

    

num_rounds = []

for i in trange(1,1000000):
    num_rounds.append(round(i))
    
print(np.mean(np.array(num_rounds)))


    

    




100%|██████████| 999999/999999 [00:28<00:00, 34761.91it/s]





    




6.00127700128