Type error when adding 1 to i (Recursion)-CodePudding

I am trying to write a recursion that sums the product of items in a list, in the pattern of:

(some_list[i] * some_list[j])   (some_list[i 1] * some_list[j-1])  
(some_list[i 2] * some_list[j-2])   ........

The limit being once every number has been accounted for between i and j.
I believe I have set up the recursion correctly (correct me if I am wrong), however I am getting the following error:

TypeError: unsupported operand type(s) for  : 'int' and 'str'

def sum_product(some_list, i, j):
    limit = len(some_list)//2
    if j <= limit:
        return ' '
    else:
        result = some_list[i]   some_list[j]
        return result   sum_product(some_list, i   1, j - 1)
print(sum_product([1, 2, 3, 4, 5, 6, 7, 8], 1, 6))

CodePudding user response：

Change to return 0 and change the to *. The limit should also be adjusted to include all numbers with indexes between i and j. Assuming j > i.

def sum_product(some_list, i, j):
    if j < i:
        return 0
    else:
        result = some_list[i] * some_list[j]
        return result   sum_product(some_list, i   1, j - 1)
print(sum_product([1, 2, 3, 4, 5, 6, 7, 8], 1, 7))

Output: 86 = 2*8 3*7 4*6 5*5