Longest Zero Sublist Sum

Given a list of integers nums, which contains either -1 or 1, return the length of the longest sublist that sums to 0.

Constraints

• n ≤ 100,000 where n is the length of nums.

https://binarysearch.com/problems/Longest-Zero-Sublist-Sum

Examples

Example 1

Input

• nums = [1, 1, 1, 1, -1, -1, 1, -1]

Output

• answer = 6

Explanation

The longest sublist that sums to 0 is [1, 1, -1, -1, 1, -1] which has length 6.

Solution