for any given list I need output as shown below
l1 = [2,3,4]
output = [2*3+ 3*4 + 4*2] = [26]
similarly
l2 = [3,4,5,7,8,3]
output = [3*4 + 4*5 + 5*7 + 7*8 + 8*3 + 3*3] = [156]
The length of the list is dynamic and so could go up to 100, and the code needs to dynamically do the calculations based on the length of the list.
Appreciate any help.
>Solution :
Rotate the list by appending the first element to a slice of everything after the first element; then zip the original list with the rotated list. Use sum to generate the actual numeric sum, and str.join with f-strings to generate the rest of the output.
>>> def rot_sum(nums):
... rot_nums = list(zip(nums, nums[1:] + [nums[0]]))
... return f"[{' + '.join(f'{a}*{b}' for a, b in rot_nums)}] = [{sum(a * b for a, b in rot_nums)}]"
...
>>> rot_sum([2, 3, 4])
'[2*3 + 3*4 + 4*2] = [26]'
>>> rot_sum([3,4,5,7,8,3])
'[3*4 + 4*5 + 5*7 + 7*8 + 8*3 + 3*3] = [156]'