Max Consecutive Ones III

from collections import deque

class Solution:
    def longestOnes(self, A: List[int], K: int) -> int:
        # Initialise longest_length to 0
        longest_length = 0

        # Initialise window starting at index 0 with left_bound and right_bound
        left_bound = 0
        right_bound = 0

        # Initialise positions of 0s to empty deque zero_indexes
        zero_indexes = deque([])

        # Iteratively increase the right_bound
        while right_bound < len(A):

            # When we see a 0
            if A[right_bound] == 0:

                # Enqueue that 0's position in zero_indexes
                zero_indexes.append(right_bound)

                # If length of zero_indexes is > K:
                if len(zero_indexes) > K:
                    # popleft from zero_indexes
                    first_zero_in_prev_window = zero_indexes.popleft()
                    # Move left bound to the first index (elem) in zero_indexes (after popping)
                    left_bound = first_zero_in_prev_window + 1

                    # Move right bound to avoid double-counting the same right bound
                    right_bound += 1

                    # Skip to next iteration of loop because longest_length can't have increased
                    continue

            # Update longest_length
            curr_window_size = right_bound - left_bound + 1
            longest_length = max(longest_length, curr_window_size)

            # Increment right bound to continue traversal
            right_bound += 1

        # Return longest length detected
        return longest_length