p8.py

# !/usr/bin/env python3

numseq = '''7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450'''

start, end = 0, 0
product = 1
max_product = -1

while True:
    if end == 1000:
        break

    num = int(numseq[end])

    if num == 0:
        start = end + 1
        end = start
        product = 1
        continue

    product *= num

    if end - start == 12:
        max_product = max(max_product, product)
        product //= int(numseq[start])
        start += 1

    end += 1

print("Result:", max_product)