Project Euler: 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 [3]:

    
import numpy as np



In [79]:

    
d1000 = '7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450'



In [146]:

    
# YOUR CODE HERE   (Late Assignment)
def great(y):                    #Changes variable to a
    a = d1000                    #empty lists to append later values
    k = []
    j = []
    for i in range(len(a)):      #Takes string a and converts it to a list of seperate intergers in the same order.
        k.append(int(a[i]))
    x = np.array(k)              #Puts list in array.
    for i in range(0, len(x)):
        v = np.prod(x[i:i+y])    #Takes product from index i to index i+y, puts it in it own array, and start again at the next index.
        j.append(v)              #Appends products to empty list
    return j
print(max(great(13)))            #Finds greatest product in list.

23514624000



In [ ]:

    
assert True # leave this for grading