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 [2]:
d1000 = """
73167176531330624919225119674426574742355349194934
96983520312774506326239578318016984801869478851843
85861560789112949495459501737958331952853208805511
12540698747158523863050715693290963295227443043557
66896648950445244523161731856403098711121722383113
62229893423380308135336276614282806444486645238749
30358907296290491560440772390713810515859307960866
70172427121883998797908792274921901699720888093776
65727333001053367881220235421809751254540594752243
52584907711670556013604839586446706324415722155397
53697817977846174064955149290862569321978468622482
83972241375657056057490261407972968652414535100474
82166370484403199890008895243450658541227588666881
16427171479924442928230863465674813919123162824586
17866458359124566529476545682848912883142607690042
24219022671055626321111109370544217506941658960408
07198403850962455444362981230987879927244284909188
84580156166097919133875499200524063689912560717606
05886116467109405077541002256983155200055935729725
71636269561882670428252483600823257530420752963450
"""
In [3]:
# get d1000 readable
d1000_str = "".join(d1000.split("\n"))
# put values into an array
d1000_ar = np.array([i for i in d1000_str], dtype = int)
# compute products of n adjacent values and keep largest
def myprod(n):
test = 0
for i in range(n,1000):
test_cur = np.prod(d1000_ar[(i-n):(i)])
if test_cur > test:
test = test_cur
return(test)
myprod(4)
myprod(13)
Out[3]:
In [4]:
assert True # leave this for grading
In [7]:
print(np.prod(np.array([3,2,4])))
print(np.array([3,2,4]).prod())