Project Euler: Problem 8

https://projecteuler.net/problem=8

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

(see the number below)

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

Use NumPy for this computation


In [1]:
import numpy as np

In [58]:
d1000 = """
73167176531330624919225119674426574742355349194934
96983520312774506326239578318016984801869478851843
85861560789112949495459501737958331952853208805511
12540698747158523863050715693290963295227443043557
66896648950445244523161731856403098711121722383113
62229893423380308135336276614282806444486645238749
30358907296290491560440772390713810515859307960866
70172427121883998797908792274921901699720888093776
65727333001053367881220235421809751254540594752243
52584907711670556013604839586446706324415722155397
53697817977846174064955149290862569321978468622482
83972241375657056057490261407972968652414535100474
82166370484403199890008895243450658541227588666881
16427171479924442928230863465674813919123162824586
17866458359124566529476545682848912883142607690042
24219022671055626321111109370544217506941658960408
07198403850962455444362981230987879927244284909188
84580156166097919133875499200524063689912560717606
05886116467109405077541002256983155200055935729725
71636269561882670428252483600823257530420752963450
"""

In [60]:
thousand_digits= """7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450
"""

i = 0 # this is my counter
list_of_thirteens=[] # this is my list of all possible 13 adjacent numbers within the 1000
while(i<=987):     #This will assure that my code will stop at the very last adjacent 13 numbers
    a= thousand_digits[i:i+13]
    list_of_thirteens.append(a) # adds the adjacent 13 numbers onto my list
    i+=1                  # shifts to right by one

products=[]
for i in list_of_thirteens: # for each element in my list, turn into integer, and multiply them together
    c=(int(i[0])*int(i[1])*int(i[2])*int(i[3])*int(i[4])*int(i[5])*int(i[6])*int(i[7])*int(i[8])*int(i[9])*int(i[10])*int(i[11])*int(i[12]))
    products.append(c) # add products to my list-- products


answer = max(products)
print(answer) # this is my answer


23514624000

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assert True # leave this for grading