8: Largest Product in a Series

The four adjacent digits in the 1000-digit number that have the greatest product are \(9\times 9\times 8\times 9\times = 5832\).

\[\begin{split} 73167176531330624919225119674426574742355349194934\\ 96983520312774506326239578318016984801869478851843\\ 85861560789112949495459501737958331952853208805511\\ 12540698747158523863050715693290963295227443043557\\ 66896648950445244523161731856403098711121722383113\\ 62229893423380308135336276614282806444486645238749\\ 30358907296290491560440772390713810515859307960866\\ 70172427121883998797908792274921901699720888093776\\ 65727333001053367881220235421809751254540594752243\\ 52584907711670556013604839586446706324415722155397\\ 53697817977846174064955149290862569321978468622482\\ 83972241375657056057490261407972968652414535100474\\ 82166370484403199890008895243450658541227588666881\\ 16427171479924442928230863465674813919123162824586\\ 17866458359124566529476545682848912883142607690042\\ 24219022671055626321111109370544217506941658960408\\ 07198403850962455444362981230987879927244284909188\\ 84580156166097919133875499200524063689912560717606\\ 05886116467109405077541002256983155200055935729725\\ 71636269561882670428252483600823257530420752963450 \end{split}\]

Find the thirteen adjacent digits in the 1000-digit number that have the greatest product. What is the value of this product?

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Your Solution

Lunch this notebook and try to create your own solution!

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def problem8(L, N):  # L = long number, N = number of adjacent digits
    # Try your solution here
    return solution

# Testing:
unittest.main(argv=[''], verbosity=2,exit=False)

# Printing Project Euler Solution
# print(problem8(13))

My solution

Spoiler Alert!!

See my solution bellow

long_digit = 7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450

def problem8(L, N):  # L = long number, N = number of adjacent digits
    long_string = str(L)
    greatest = 0
    M = len(long_string) - N + 1
    for i in range(M):
        # get a chunk of the number
        short = long_string[i:i+N]

        # calculate the product
        product = 1
        for n in short:
            product *= int(n)

        # keep the largest value
        greatest = max(product, greatest)

    return greatest

# Testing
unittest.main(argv=[''], verbosity=2,exit=False)

Add main question:

# Printing Project Euler Solution
problem8(long_digit, 13)

23514624000