video explanation https www youtube comwatch v6w60zi1ntl8featureemblogo find the maximum nonadjacent sum of the integers in the nums input list maximumnonadjacentsum1 2 3 4 maximumnonadjacentsum1 5 3 7 2 2 6 18 maximumnonadjacentsum1 5 3 7 2 2 6 0 maximumnonadjacentsum499 500 3 7 2 2 6 500 video explanation https www youtube com watch v 6w60zi1ntl8 feature emb_logo find the maximum non adjacent sum of the integers in the nums input list maximum_non_adjacent_sum 1 2 3 4 maximum_non_adjacent_sum 1 5 3 7 2 2 6 18 maximum_non_adjacent_sum 1 5 3 7 2 2 6 0 maximum_non_adjacent_sum 499 500 3 7 2 2 6 500
from __future__ import annotations


def maximum_non_adjacent_sum(nums: list[int]) -> int:
    
    if not nums:
        return 0
    max_including = nums[0]
    max_excluding = 0
    for num in nums[1:]:
        max_including, max_excluding = (
            max_excluding + num,
            max(max_including, max_excluding),
        )
    return max(max_excluding, max_including)


if __name__ == "__main__":
    import doctest

    doctest.testmod()