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What order is best?

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Here I have a list of 4 numbers:

>>> my_numbers = [-1, 5, 10, 21]

Here I have another list of 4 numbers:

>>> your_numbers = [3, 0, -10, 15]

Here is a function, that takes each element in the two lists, multiplies them, and retuns the sum.

>>> def list_product(first_list, second_list):
...     product = 0
...     for i in range(len(first_list)):
...         value = first_list[i] * second_list[i]
...         product = product + value
...     return product

Let’s see the list_product for our two lists:

>>> list_product(my_numbers, your_numbers)
212

Now - here is your problem. You can shuffle the second list, your_numbers, in any way you like. What is the right order for the numbers in your_numbers, to give the highest value for the list_product?

For example, here I’m doing a random shuffle of the list:

>>> #: The random module
>>> import random

>>> random.shuffle(your_numbers)
>>> your_numbers
[15, 0, -10, 3]

And I calculate the list product again:

>>> list_product(my_numbers, your_numbers)
-52

See if you can find the best ordering to give the highest sum.

If you’ve done that, see if you can find the best ordering for the lowest sum.