problem_008.py

# https://projecteuler.net/problem=8
import math
import unittest

NUMBER = """
73167176531330624919225119674426574742355349194934
96983520312774506326239578318016984801869478851843
85861560789112949495459501737958331952853208805511
12540698747158523863050715693290963295227443043557
66896648950445244523161731856403098711121722383113
62229893423380308135336276614282806444486645238749
30358907296290491560440772390713810515859307960866
70172427121883998797908792274921901699720888093776
65727333001053367881220235421809751254540594752243
52584907711670556013604839586446706324415722155397
53697817977846174064955149290862569321978468622482
83972241375657056057490261407972968652414535100474
82166370484403199890008895243450658541227588666881
16427171479924442928230863465674813919123162824586
17866458359124566529476545682848912883142607690042
24219022671055626321111109370544217506941658960408
07198403850962455444362981230987879927244284909188
84580156166097919133875499200524063689912560717606
05886116467109405077541002256983155200055935729725
71636269561882670428252483600823257530420752963450
""".replace('\n', '')


def chunk(seq, chunk_size):
    chunks = []
    first, last = 0, chunk_size
    while last < len(seq):
        chunks.append(seq[first:last])
        first = last
        last += chunk_size
    return chunks

def largest_product_in_series(n, serie_of_m):
    parsed_number = [int(pn) for pn in NUMBER]
    largest_product = 0

    while len(parsed_number) > serie_of_m:
        parsed_number_chunked = chunk(parsed_number, serie_of_m)
        products = map(
            lambda seq_chunked:
                reduce(
                    lambda acc, x: acc*x,seq_chunked), parsed_number_chunked)
        max_products = max(products)
        if max_products > largest_product:
            largest_product = max_products
        parsed_number.pop(0)

    return largest_product


class TestSmallestMultiple(unittest.TestCase):

    def test_1_1(self):
        self.assertEqual(largest_product_in_series(NUMBER, 4), 5832)

    def test_1_2(self):
        self.assertEqual(largest_product_in_series(NUMBER, 13), 5832)


if __name__ == '__main__':
    unittest.main()