# The four adjacent digits in the 1000-digit number that have the greatest
# product are 9 × 9 × 8 × 9 = 5832. Find the thirteen adjacent digits in the
# 1000-digit number that have the greatest product. What is the value of this
# product?


thousand_digit_number = (
    '73167176531330624919225119674426574742355349194934'
    '96983520312774506326239578318016984801869478851843'
    '85861560789112949495459501737958331952853208805511'
    '12540698747158523863050715693290963295227443043557'
    '66896648950445244523161731856403098711121722383113'
    '62229893423380308135336276614282806444486645238749'
    '30358907296290491560440772390713810515859307960866'
    '70172427121883998797908792274921901699720888093776'
    '65727333001053367881220235421809751254540594752243'
    '52584907711670556013604839586446706324415722155397'
    '53697817977846174064955149290862569321978468622482'
    '83972241375657056057490261407972968652414535100474'
    '82166370484403199890008895243450658541227588666881'
    '16427171479924442928230863465674813919123162824586'
    '17866458359124566529476545682848912883142607690042'
    '24219022671055626321111109370544217506941658960408'
    '07198403850962455444362981230987879927244284909188'
    '84580156166097919133875499200524063689912560717606'
    '05886116467109405077541002256983155200055935729725'
    '71636269561882670428252483600823257530420752963450'
)


def generate_digits(count: int) -> str:
    bottom = 0
    top = count
    maximum = len(thousand_digit_number)

    while top <= maximum:
        yield thousand_digit_number[bottom:top]

        bottom += 1
        top += 1


def find_largest_product(count: int) -> (str, int):
    largest = 0
    largest_digits = ''

    for digits in generate_digits(count):
        product = 1
        for i in digits:
            product *= int(i)

        if product > largest:
            largest = product
            largest_digits = digits

    return largest_digits, largest


if __name__ == '__main__':
    largest_digits, largest = find_largest_product(13)
    print(f'Largest product is {largest} with digits {largest_digits}')
