Vfrdtyky

I'm trying to find write a function that gives the product of the highest pair of adjacent elements in a list. For my code,

gala = [1, 2, 3, 4, 5]

def adjacentElementsProduct(inputArray):

    for i in range(len(inputArray)):

        if inputArray[i] * inputArray[i+1] > inputArray[i+1] * inputArray[i+2]:

            return  inputArray[i] * inputArray[i+1] 

    elif inputArray[i+1] * inputArray[i+2] > inputArray[i] * inputArray[i+1] and inputArray[i+1] * inputArray[i+2] > inputArray[i+2] * inputArray[i+3]:

        return  inputArray[i+1] * inputArray[i+2]

    elif inputArray[i+2] * inputArray[i+3] > inputArray[i+1] * inputArray[i+2] and inputArray[i+2] * inputArray[i+3] > inputArray[i+3] * inputArray[i+4]:

         return  inputArray[i+2] * inputArray[i+3]

    else:

        return inputArray[i+3] * inputArray[i+4] 

return adjacentElementsProduct



adjacentElementsProduct(gala)

Here the output would be 20 (since 4 x 5 is the highest adjacent pairs). This function works for the given list even if I change the order of the numbers and their sign. However, if the length of the list is changed then the code breaks. If the list was

gala = [1, -6]

or

gala = [2, 5, 7, -9, 10, 0, 11]

I wanted the function first list's output to would be -6 and second would be 35. But my function breaks for such lists.

If i did correctly understood your issue, i think your function can be reduced to:

def adjacentElementsProduct(elm):

   if len(elm) < 2:

       return None

   return max(k*v for k, v in zip(elm, elm[1:]))

So:

>>> adjacentElementsProduct([1, 2, 3, 4, 5])

20

>>> adjacentElementsProduct([1, -6])

-6

>>> adjacentElementsProduct([2, 5, 7, -9, 10, 0, 11])

35

A modification of @ChihebNexus's approach:

from operator import mul



def adjacentElementsProduct(elm):

   if len(elm) < 2:

       return None

   return max(map(mul, elm, elm[1:]))

An even shorter version:

def adjacentElementsProduct(elm):

   return max(map(mul, elm, elm[1:])) if len(elm) < 2 else None

And another one:

from operator import mul

from itertools import starmap



def adjacentElementsProduct(elm):

   if len(elm) < 2:

       return None

   return max(starmap(mul, zip(elm, elm[1:])))