1004. Max Consecutive Ones III

https://leetcode.com/problems/max-consecutive-ones-iii/

Python

Sliding Window

class Solution:
    def longestOnes(self, nums: List[int], k: int) -> int:
        left, right = 0, 0
        while right < len(nums):
            k -= 1 - nums[right]
            if k < 0:
                k += 1 - nums[left]
                left += 1
            right += 1

        return right - left

Prefix Sum

Solution from glfox

class Solution:
    def longestOnes(self, nums: List[int], k: int) -> int:
        if not nums:
            return 0

        zero_idx = {i:-1 for i in range(-k, 1)}
        ans, zeros = 0, 0
        for i in range(len(nums)):
            if nums[i] == 0:
                zeros += 1
                zero_idx[zeros] = i
            ans = max(ans, i - zero_idx[zeros - k])

        return ans