c19.sagews

3+4

7

def coin_flip():
    if random() < .5:
        return "H"
    else:
        return "T"
    
def coin_flips(n):
    flip_results = []
    for i in [1..n]:
        flip_results.append(coin_flip())
    return flip_results    


def number_of_heads(n):
    flip_results = coin_flips(n)
    heads = 0
    for i in flip_results:
        if i == "H":
            heads = heads+1
    return heads  

def longest_run_of_heads(n):
    flip_results = coin_flips(n)
    print flip_results
    count = 0
    longest = 0
    for i in [0..(n-1)]:
        if flip_results[i] == "H":
            count = count+1
            if count > longest:
                longest = count
        else:
            count = 0
    return longest       

longest_run_of_heads(10)

['H', 'T', 'H', 'H', 'T', 'H', 'T', 'T', 'T', 'T'] 2

longest_run_of_heads(10)

['T', 'T', 'T', 'T', 'H', 'T', 'T', 'T', 'H', 'H'] 2

longest_run_of_heads(10)

['H', 'H', 'H', 'T', 'T', 'T', 'T', 'H', 'T', 'H'] 3

longest_run_of_heads(10)

['T', 'H', 'H', 'T', 'T', 'H', 'H', 'T', 'T', 'T'] 2

longest_run_of_heads(10)

['H', 'H', 'T', 'H', 'T', 'H', 'H', 'T', 'H', 'H'] 2

longest_run_of_heads(10)

['T', 'T', 'T', 'H', 'H', 'T', 'T', 'H', 'T', 'H'] 2

longest_run_of_heads(10)

['H', 'H', 'T', 'T', 'H', 'T', 'H', 'H', 'H', 'H'] 4