BinarySearch 0884 Index with Equal Left and Right Sums

Problem statement

https://binarysearch.com/problems/Index-with-Equal-Left-and-Right-Sums/

Solution

Equal to Leetcode 1991. Find the Middle Index in Array.

Complexity

It is O(n) for time and space.

Code

class Solution:
    def solve(self, nums):
        acc = [0] + list(accumulate(nums))
        n = len(nums)
        for i in range(n):
            if acc[i] == acc[-1] - acc[i+1]: return i
        return -1