Given a binary array nums, you should delete one element from it.
Return the size of the longest non-empty subarray containing only 1's in the resulting array.
Return 0 if there is no such subarray.
 
Example 1:
Input: nums = [1,1,0,1]
Output: 3
Explanation: After deleting the number in position 2, [1,1,1] contains 3 numbers with value of 1's.
Example 2:
Input: nums = [0,1,1,1,0,1,1,0,1]
Output: 5
Explanation: After deleting the number in position 4, [0,1,1,1,1,1,0,1] longest subarray with value of 1's is [1,1,1,1,1].
Example 3:
Input: nums = [1,1,1]
Output: 2
Explanation: You must delete one element.
Example 4:
Input: nums = [1,1,0,0,1,1,1,0,1]
Output: 4

Example 5:
Input: nums = [0,0,0]
Output: 0

 
Constraints:

1 <= nums.length <= 10^5
nums[i] is either 0 or 1.

Difficulty: MEDIUM
Tags: Dynamic programming

Data structures

Amortized analysis
Skill types: Dynamic programming

Amortized analysis

Data structures

Starter code:
class Solution:
    def longestSubarray(self, nums: List[int]) -> int:
        

Solutions:
class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		if not 0 in nums:
			return len(nums) - 1
		ans = 0
		tot = 0
		prev = 0
		for n in nums:
			if n == 1:
				tot += 1
			else:
				ans = max(tot + prev, ans)
				prev = tot
				tot = 0
		return max(prev + tot, ans)


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		z = [0]
		l = []
		a = 0
		c = 0
		for i in range(len(nums)):
			if a == 1 and nums[i] == 0:
				z.append(c)
				c = i - (l[-1] + 1)
				a = 1
				l.append(i)
			elif nums[i] == 0:
				a = a + 1
				l.append(i)
			elif nums[i] == 1:
				c = c + 1
		z.append(c)
		if nums.count(1) == len(nums):
			return len(nums) - 1
		return max(z)


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		(zc, oc) = (0, 0)
		for (i, v) in enumerate(nums):
			if v:
				oc += 1
			else:
				zc += 1
		if oc == len(nums):
			return oc - 1
		elif zc == len(nums):
			return 0
		elif zc == 1:
			return oc
		elif oc == 1:
			return 1
		else:
			l = r = 0
			for (i, v) in enumerate(nums):
				if v == 1:
					l += 1
				else:
					break
			st = i + 1
			po = i
			(maxo, maxi) = (-1, -1)
			while st < len(nums):
				if nums[st] == 1:
					r += 1
					st += 1
					continue
				else:
					v = l + r
					if maxo < v:
						maxo = v
						maxi = po
					po = st
					l = r
					r = 0
					st += 1
			maxo = max(maxo, l + r)
			return maxo


from collections import deque

class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		n = len(nums)
		if n == 0:
			return 0
		elif n == 1:
			return 0 if nums[0] == 0 else 1
		q = deque()
		num_z = 0
		maxx = 0
		is_0 = 0
		for i in range(n):
			if nums[i] == 1:
				q.append(i)
				continue
			is_0 = 1
			if num_z < 1:
				q.append(i)
				num_z += 1
				maxx = max(maxx, len(q) - 1)
				continue
			maxx = max(maxx, len(q) - 1)
			while q and num_z == 1:
				top = q.popleft()
				if nums[top] == 0:
					num_z -= 1
			q.append(i)
			num_z += 1
		if is_0 == 0:
			return n - 1
		maxx = max(len(q) - num_z, maxx)
		return maxx


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		c = 0
		ind = 0
		for i in range(len(nums)):
			if nums[i] == 0:
				j = i + 1
				k = 0
				while j < len(nums) and nums[j] == 1:
					k += 1
					j += 1
				j = i - 1
				while j >= 0 and nums[j] == 1:
					k += 1
					j -= 1
				if k > c:
					c = k
					ind = i
		if ind == 0 and nums[ind] == 1:
			ind = len(nums) - 1
			c = len(nums) - 1
		return c


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		res = zeros = 0
		zero_i = None
		i = 0
		for (j, v) in enumerate(nums):
			if v == 0:
				zeros += 1
				if zeros == 2:
					i = zero_i + 1
					zeros = 1
				zero_i = j
			res = max(res, j - i)
		return res


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		max_length = 0
		count = 0
		for num in nums:
			if num == 1:
				count += 1
				max_length = max(max_length, count)
			else:
				count = 0
		if max_length == len(nums):
			return len(nums) - 1
		elif max_length == 0:
			return 0
		num_left = 0
		num_right = 0
		for (i, num) in enumerate(nums):
			if num == 1:
				num_right += 1
			else:
				max_length = max(max_length, num_left + num_right)
				if i + 1 < len(nums) and nums[i + 1] == 1:
					num_left = num_right
					num_right = 0
				else:
					num_left = 0
					num_right = 0
		max_length = max(max_length, num_left + num_right)
		return max_length


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		(start, end, maxlen, k) = (0, 0, 0, 1)
		while end < len(nums):
			if nums[end] == 0:
				k = k - 1
			if k < 0:
				if nums[start] == 0:
					k += 1
				start = start + 1
				end = end + 1
				continue
			if k >= 0 or nums[end] == 1:
				maxlen = max(maxlen, end - start)
				end = end + 1
		return maxlen


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		longest = 0
		left = 0
		x = 1
		for right in range(len(nums)):
			if not nums[right]:
				x -= 1
			while x < 0:
				if not nums[left]:
					x += 1
				left += 1
			longest = max(longest, right - left + 1)
		return longest - 1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		noofones = 0
		m = 0
		lastoneslen = 0
		for i in nums:
			if i == 1:
				noofones += 1
			else:
				m = max(m, noofones + lastoneslen)
				lastoneslen = noofones
				noofones = 0
		m = max(m, noofones + lastoneslen)
		if m == len(nums):
			m -= 1
		return m


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		max_count = 0
		start = 0
		zero = 2
		for i in range(len(nums)):
			if nums[i] == 0:
				zero -= 1
			while zero < 1:
				if nums[start] == 0:
					zero += 1
				start += 1
			max_count = max(max_count, i - start)
		return max_count


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		res = []
		count = 0
		for (i, val) in enumerate(nums):
			if val == 0:
				if count > 0:
					res.append(count)
					count = 0
				res.append(0)
			elif val == 1:
				count += 1
		if count > 0:
			res.append(count)
		lenRes = len(res)
		ma = 0
		if lenRes > 2:
			for i in range(1, lenRes - 1):
				ma = max(max(ma, res[i - 1] + res[i + 1]), max(res[i - 1], res[i]), max(res[i + 1], res[i]))
			return ma
		elif lenRes == 1 and res[0] > 0:
			return res[0] - 1
		elif lenRes == 1 and res[0] == 0:
			return ma
		elif lenRes == 2:
			return max(res[0], res[1])


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		zero = -1
		k = 1
		maxi = 0
		count = 0
		i = 0
		while i != len(nums):
			if nums[i] == 0:
				if k == 0:
					i = zero + 1
					zero = i
					maxi = max(count, maxi)
					count = 0
					k = 1
				else:
					k -= 1
					zero = i
					i += 1
			else:
				count += 1
				i += 1
		maxi = max(count, maxi)
		if maxi == len(nums):
			return maxi - 1
		else:
			return maxi


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		start = end = zeros = ones = maxx = 0
		while end < len(nums):
			if nums[end] == 1:
				ones += 1
			elif nums[end] == 0:
				zeros += 1
			while zeros > 1:
				if nums[start] == 0:
					zeros -= 1
				start += 1
			maxx = max(maxx, end - start)
			end += 1
		return maxx


class Solution:

	def longestSubarray(self, array: List[int]) -> int:
		i = 0
		lenght = 0
		stack = deque()
		zero = False
		while i < len(array):
			if array[i] == 1:
				stack.append(array[i])
				i += 1
			elif zero == False:
				stack.append(array[i])
				zero = True
				i += 1
			else:
				temp = len(stack) - 1
				if temp > lenght:
					lenght = temp
				while stack[0] != 0:
					stack.popleft()
				stack.popleft()
				zero = False
			if len(stack) > lenght:
				lenght = len(stack) - 1
		return lenght


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		left = 0
		right = 0
		zeroes = 1
		res = 0
		while right < len(nums):
			if nums[right] == 0:
				zeroes -= 1
			while zeroes < 0:
				if nums[left] == 0:
					zeroes += 1
				left += 1
			res = max(res, right - left)
			right += 1
		return res


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		(i, j) = (0, 0)
		(ans, cur) = (0, 0)
		while j < len(nums):
			cur += nums[j]
			while i < j and cur < j - i:
				cur -= nums[i]
				i += 1
			ans = max(ans, cur)
			j += 1
		return min(ans, len(nums) - 1)


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		n = len(nums)
		if n == 0:
			return 0
		joined = [0 for i in range(n)]
		left = 0
		right = 0
		for i in range(n):
			joined[i] += left
			joined[n - 1 - i] += right
			if nums[i] == 1:
				left += 1
			else:
				left = 0
			if nums[n - 1 - i] == 1:
				right += 1
			else:
				right = 0
		return max(joined)


class Solution:

	def longestSubarray(self, nums):
		n = len(nums)
		last_zero = None
		last_one = None
		cnt = 0
		res = 0
		for i in range(n):
			if nums[i] == 1:
				if last_one is None:
					last_one = i
				cnt += 1
			elif last_zero is None:
				last_zero = i
			else:
				last_one = last_zero + 1
				last_zero = i
				cnt = i - last_one
			res = max(res, cnt)
		if res == n:
			return n - 1
		return res


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		mc = 0
		onep = False
		for i in range(len(nums)):
			if nums[i] == 0:
				c = 0
				j = i - 1
				while j >= 0 and nums[j] != 0:
					j -= 1
					c += 1
				j = i + 1
				while j < len(nums) and nums[j] != 0:
					j += 1
					c += 1
				if c > mc:
					mc = c
			else:
				onep = True
		if onep and mc == 0:
			return len(nums) - 1
		elif not onep and mc == 0:
			return 0
		else:
			return mc


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		groups = [[k, len(list(g))] for (k, g) in itertools.groupby(nums)]
		if len(groups) == 1:
			return groups[0][1] - 1 if groups[0][0] else 0
		ans = 0
		for i in range(len(groups)):
			(k, klen) = groups[i]
			if k:
				ans = max(ans, klen)
			elif i not in [0, len(groups) - 1] and klen == 1:
				ans = max(ans, groups[i - 1][1] + groups[i + 1][1])
		return ans


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		(low, high) = (0, 0)
		cn = 0
		ans = 0
		while low < len(nums) and high < len(nums):
			if nums[high] == 0:
				if cn < 1:
					cn += 1
				else:
					while nums[low] != 0:
						low += 1
					low += 1
			high += 1
			ans = max(ans, high - low)
		return max(ans, high - low) - 1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		if not nums:
			return 0
		if all(nums):
			return len(nums) - 1
		n = len(nums)
		dp = [[0] * 2 for _ in range(n)]
		dp[0][0] = 1 if nums[0] == 1 else 0
		dp[0][1] = 0
		res = 0
		for i in range(1, n):
			if nums[i] == 1:
				dp[i][0] = dp[i - 1][0] + 1
				dp[i][1] = dp[i - 1][1] + 1
			else:
				dp[i][0] = 0
				dp[i][1] = dp[i - 1][0]
			res = max(res, dp[i][1], dp[i][0])
		return res


class Solution:

	def longestSubarray(self, A):
		if not A:
			return 0
		n = len(A)
		right = 0
		cnt = 0
		res = 0
		for left in range(n):
			while right <= n - 1 and (cnt == 0 or A[right] == 1):
				cnt += A[right] == 0
				right += 1
			res = max(res, right - left)
			cnt -= A[left] == 0
		return res - 1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		left = []
		total = 0
		for n in nums:
			if n == 0:
				total = 0
			else:
				total += n
			left.append(total)
		right = []
		total = 0
		for i in range(len(nums) - 1, -1, -1):
			if nums[i] == 0:
				total = 0
			else:
				total += nums[i]
			right.append(total)
		right = right[::-1]
		curMax = 0
		for i in range(len(nums) - 2):
			curMax = max(left[i] + right[i + 2], curMax)
		return curMax


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		n = len(nums)
		(l, r) = ([0] * n, [0] * n)
		for i in range(1, n):
			l[i] = l[i - 1] + 1 if nums[i - 1] == 1 else 0
		for i in range(n - 2, -1, -1):
			r[i] = r[i + 1] + 1 if nums[i + 1] == 1 else 0
		ans = max(r[0], l[n - 1])
		for i in range(1, n - 1):
			ans = max(ans, l[i] + r[i])
		return ans


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		k = 1
		i = 0
		for j in range(len(nums)):
			if nums[j] == 0:
				k -= 1
			if k < 0:
				if nums[i] == 0:
					k += 1
				i += 1
		return j - i


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		prevStart = -1
		candidates = []
		if 0 not in nums:
			return len(nums) - 1
		for i in range(len(nums)):
			if nums[i] == 1:
				if prevStart == -1:
					prevStart = i
					continue
			elif prevStart != -1:
				candidates.append([prevStart, i - 1])
				prevStart = -1
		if prevStart != -1:
			candidates.append([prevStart, len(nums) - 1])
		res = [0]
		for i in range(len(candidates)):
			if i == len(candidates) - 1:
				res.append(candidates[i][1] - candidates[i][0] + 1)
			elif candidates[i + 1][0] - candidates[i][1] == 2:
				res.append(candidates[i + 1][1] - candidates[i][0])
			else:
				res.append(candidates[i][1] - candidates[i][0] + 1)
		return max(res)


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		i = 0
		j = 0
		sum = 0
		ans = 0
		for (j, val) in enumerate(nums):
			sum += val
			while i < j and sum < j - i:
				sum -= nums[i]
				i += 1
			ans = max(ans, j - i)
		return ans


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		n = len(nums)
		leftones = [0] * n
		for i in range(n):
			if nums[i] == 0:
				leftones[i] = 0
			else:
				leftones[i] = 1 if i == 0 else leftones[i - 1] + 1
		rightones = [0] * n
		for i in range(n - 1, -1, -1):
			if nums[i] == 0:
				rightones[i] = 0
			else:
				rightones[i] = 1 if i == n - 1 else rightones[i + 1] + 1
		res = 0
		for i in range(1, n - 1):
			res = max(res, leftones[i - 1] + rightones[i + 1])
		return res


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		(prev, curr, best) = (0, 0, 0)
		n = len(nums)
		for (i, x) in enumerate(nums):
			if x == 0:
				best = max(best, prev + curr)
				if i == n - 1:
					pass
				elif nums[i + 1] == 1:
					prev = curr
					curr = 0
				else:
					prev = 0
					curr = 0
			else:
				curr += 1
		best = max(best, prev + curr)
		if best == n:
			best -= 1
		return best


class Solution:

	def longestSubarray(self, xs: List[int]) -> int:
		n = len(xs)
		if n < 2:
			return 0
		dp = collections.deque()
		best = 0
		for (i, x) in enumerate(xs):
			if x:
				dp.append(i)
			while dp and i - dp[0] - len(dp) + 1 > 1:
				dp.popleft()
			nholes = i - dp[0] - len(dp) + 1 if dp else 1
			this_len = len(dp) - (not dp[0] and (not nholes)) if dp else 0
			best = max(best, this_len)
		return best


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		(prev, _next, n) = ([0 for _ in range(len(nums))], [0 for _ in range(len(nums))], len(nums))
		count = 0
		for i in range(n):
			num = nums[i]
			if i == 0:
				if num:
					count = 1
			elif num:
				prev[i] = count
				count += 1
			else:
				prev[i] = count
				count = 0
		count = 0
		for i in range(n - 1, -1, -1):
			num = nums[i]
			if i == n - 1:
				if num:
					count = 1
			elif num:
				_next[i] = count
				count += 1
			else:
				_next[i] = count
				count = 0
		_max = 0
		for i in range(n):
			num = nums[i]
			_max = max(_max, prev[i] + _next[i])
		return _max


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		if all(nums):
			return len(nums) - 1
		m = pre = l = pl = 0
		for (i, n) in enumerate(nums):
			if n == pre == 1:
				l += 1
			elif n == pre == 0:
				pl = 0
			elif n == 1 != pre:
				l = 1
			else:
				m = max(m, pl + l)
				pl = l
			pre = n
		return max(m, pl + l) if pre == 1 else m


def get_longest(nums):
	arr = [1 - x for x in nums]
	(l, r) = (0, 0)
	count = 0
	max_length = 0
	while l < len(arr):
		if r == len(arr):
			step = 'l'
		elif l == r:
			step = 'r'
		elif count + arr[r] > 1:
			step = 'l'
		else:
			step = 'r'
		if step == 'l':
			count -= arr[l]
			l += 1
		else:
			count += arr[r]
			r += 1
			max_length = max(max_length, r - l)
	return max(0, max_length - 1)

class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		return get_longest(nums)


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		new_array = list()
		current_segment = 0
		for num in nums:
			if num == 0:
				if current_segment > 0:
					new_array.append(current_segment)
					current_segment = 0
				new_array.append(0)
			else:
				current_segment += 1
		if current_segment > 0:
			new_array.append(current_segment)
		max_length = 0
		for idx in range(len(new_array)):
			max_length = max(max_length, new_array[idx])
			if idx > 0 and idx < len(new_array) - 1 and (new_array[idx] == 0):
				if new_array[idx - 1] > 0 and new_array[idx + 1] > 0:
					max_length = max(max_length, new_array[idx - 1] + new_array[idx + 1])
		if max_length == len(nums):
			return max_length - 1
		else:
			return max_length


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		right = [0 for _ in range(len(nums))]
		left = [0 for _ in range(len(nums))]
		for i in range(1, len(nums)):
			if nums[i - 1] == 1:
				left[i] = 1 + left[i - 1]
		res = float('-inf')
		for i in range(len(nums) - 2, -1, -1):
			if nums[i + 1] == 1:
				right[i] = 1 + right[i + 1]
			res = max(res, left[i] + right[i])
		return res


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		se = set(nums)
		if 0 not in se:
			return len(nums) - 1
		elif 1 not in se:
			return 0
		count = 0
		flag = 0
		ls = []
		for i in nums:
			if i == 0:
				if flag == 0:
					count += 1
				else:
					flag = 0
					ls.append(count)
					count = 1
			elif flag == 1:
				count += 1
			else:
				flag = 1
				ls.append(count)
				count = 1
		ls.append(count)
		ind = 0
		ans = 0
		while ind < len(ls):
			if ls[ind] != 0:
				if ls[ind] == 1:
					if ind == 0 and ind < len(ls) - 1:
						ans = max(ans, ls[ind + 1])
					elif ind == len(ls) - 1 and ind > 0:
						ans = max(ans, ls[ind - 1])
					elif ind < len(ls) - 1 and ind > 0:
						ans = max(ans, ls[ind - 1] + ls[ind + 1])
				elif ind == 0 and ind < len(ls) - 1:
					ans = max(ans, ls[ind + 1])
				elif ind == len(ls) - 1 and ind > 0:
					ans = max(ans, ls[ind - 1])
				elif ind < len(ls) - 1 and ind > 0:
					ans = max(ans, max(ls[ind - 1], ls[ind + 1]))
			ind += 2
		return ans


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		var = 0
		count = 0
		max1 = 0
		pos = 0
		flag = 0
		for i in nums:
			if i == 1:
				flag = 1
				if var == 1:
					pos = pos + 1
				count = count + 1
				max1 = max(count, max1)
			elif i == 0 and var == 1:
				count = pos
				pos = 0
			elif flag == 1:
				if var == 0:
					var = var + 1
				else:
					count = pos
		if max1 == len(nums):
			return max1 - 1
		return max1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		deleted = False
		(max_, cur_cnt, last_cnt) = (0, 0, 0)
		(idx, size) = (0, len(nums))
		while idx < size and nums[idx] == 0:
			idx += 1
		for i in range(idx, size):
			if nums[i] == 1:
				cur_cnt += 1
				max_ = max(max_, cur_cnt)
			else:
				if not deleted:
					deleted = True
				else:
					cur_cnt -= last_cnt
				last_cnt = cur_cnt
		if size == sum(nums):
			return size - 1
		return max_


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		if 1 not in nums:
			return 0
		if 0 not in nums:
			return len(nums) - 1
		new = []
		i = 0
		n = len(nums)
		while i < n:
			if nums[i] == 1:
				cnt = 0
				while i < n and nums[i] == 1:
					cnt += 1
					i += 1
				new.append(cnt)
			else:
				new.append(0)
				i += 1
		mx = max(new)
		for i in range(1, len(new) - 1):
			if new[i] == 0:
				mx = max(mx, new[i - 1] + new[i + 1])
		return mx


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		if len(nums) < 1:
			return 0
		res = 0
		logs = []
		for x in nums:
			if x == 0:
				logs.append(res)
				res = 0
			else:
				res += 1
		logs.append(res)
		if len(logs) == 1:
			return max(0, logs[0] - 1)
		return max([logs[i] + logs[i + 1] for i in range(len(logs) - 1)])


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		if sum(nums) >= len(nums) - 1:
			return len(nums) - 1
		l = 0
		while nums[l] == 0:
			l += 1
			if l == len(nums):
				return 0
		r = l + 1
		sum_total = nums[l]
		res = 0
		for r in range(r, len(nums)):
			sum_total += nums[r]
			if sum_total == r - l - 1:
				res = max(res, sum_total)
				while sum_total < r - l:
					sum_total -= nums[l]
					l += 1
		return max(res, sum_total)


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		if len(nums) < 2:
			return 0
		len1_prev = 0
		len1 = 0
		i = 0
		res = 0
		zc = 0
		while i < len(nums):
			if nums[i] == 1:
				len1 += 1
			else:
				res = max(res, len1 + len1_prev)
				if zc == 0:
					len1_prev = len1
					len1 = 0
					zc = 1
				elif zc == 1:
					if len1 > 0:
						len1_prev = len1
						len1 = 0
						zc = 1
					else:
						len1 = 0
						len1_prev = 0
						zc = 0
			i += 1
		res = max(res, len1 + len1_prev)
		res = min(len(nums) - 1, res)
		return res


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		n = len(nums)
		if sum(nums) == n:
			return n - 1
		dp = [[0 for x in range(len(nums))] for y in range(2)]
		dp[0][0] = 1 if nums[0] == 1 else 0
		for i in range(1, len(nums)):
			if nums[i] == 0:
				dp[0][i] = 0
				dp[1][i] = dp[0][i - 1]
			else:
				dp[0][i] = dp[0][i - 1] + 1
				dp[1][i] = dp[1][i - 1] + 1
		return max([i for x in dp for i in x])


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		max_len = 0
		zero_seen = False
		for i in range(len(nums)):
			length = 0
			if nums[i] == 0:
				zero_seen = True
				(l, r) = (i - 1, i + 1)
				while l >= 0 and nums[l] == 1:
					length += 1
					l -= 1
				while r < len(nums) and nums[r] == 1:
					length += 1
					r += 1
				max_len = max(max_len, length)
		return max_len if zero_seen else len(nums) - 1


class Solution:

	def longestSubarray(self, a: List[int]) -> int:
		ones = 0
		old_ones = 0
		maxlen = 0
		n = len(a)
		for i in range(n):
			if a[i] == 1:
				ones += 1
				maxlen = max(maxlen, ones + old_ones)
			else:
				old_ones = ones
				ones = 0
		return maxlen if ones < n else n - 1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		seq = [0]
		prev = 0
		res = 0
		for n in nums:
			if n:
				seq[-1] += 1
				res = max(prev + seq[-1], res)
			else:
				prev = seq[-1]
				seq.append(0)
		if len(seq) == 1:
			res -= 1
		return res


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		(prev, res, curr) = (0, 0, 0)
		for i in range(len(nums)):
			if nums[i] == 1:
				curr += 1
			else:
				if i < len(nums) - 1 and nums[i + 1] != 0:
					prev = curr
				else:
					prev = 0
				curr = 0
			res = max(res, curr + prev)
		if res == len(nums):
			res -= 1
		return res


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		s = []
		i = 0
		while i < len(nums):
			if nums[i] == 0:
				s.append(0)
				i += 1
			else:
				j = i
				cnt = 0
				while j < len(nums) and nums[j] == 1:
					cnt += 1
					j += 1
				s.append(cnt)
				i = j
		print(s)
		if s[0] == len(nums):
			return len(nums) - 1
		maxYet = max(s[0], s[len(s) - 1])
		for i in range(1, len(s) - 1):
			if s[i] == 0:
				maxYet = max(maxYet, s[i - 1] + s[i + 1])
			else:
				maxYet = max(maxYet, s[i])
		return maxYet


import re
import numpy as np

class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		nums = np.array(nums)
		zeros_ = np.where(nums == 0)[0]
		if zeros_.tolist():
			temp = 0
			for ind in zeros_:
				ind_ = max([ind - 1, 0])
				ind__ = min([ind + 1, len(nums) - 1])
				count_ = 0
				count__ = 0
				if nums[ind_] == 1:
					while ind_ >= 0 and nums[ind_] == 1:
						count_ += 1
						ind_ -= 1
				if nums[ind__] == 1:
					while ind__ < len(nums) and nums[ind__] == 1:
						count__ += 1
						ind__ += 1
				temp = max([count_ + count__, temp])
			return temp
		elif len(zeros_) == len(nums):
			return 0
		else:
			return len(nums) - 1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		i = 0
		ints = []
		while i < len(nums):
			start = i
			end = i
			while i < len(nums) and nums[i] == 1:
				i += 1
				end += 1
			if start != end:
				ints.append((start, end))
			i += 1
		if len(ints) == 1:
			diff = ints[0][1] - ints[0][0]
			if diff == len(nums):
				return diff - 1
			else:
				return diff
		elif not ints:
			return 0
		max_ones = 0
		for seq in range(len(ints) - 1):
			seq1 = ints[seq]
			seq2 = ints[seq + 1]
			length = None
			if seq2[0] - seq1[1] == 1:
				length = seq1[1] - seq1[0] + (seq2[1] - seq2[0])
			else:
				length = max(seq1[1] - seq1[0], seq2[1] - seq2[0])
			if length > max_ones:
				max_ones = length
		return max_ones


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		n = len(nums)
		prev = 0
		cnt = 0
		pmax = 0
		for i in range(0, n):
			if nums[i] == 1:
				cnt += 1
			else:
				prev = cnt
				cnt = 0
			maxm = prev + cnt
			if maxm > pmax:
				pmax = maxm
		if cnt == n:
			return n - 1
		else:
			return maxm if maxm > pmax else pmax


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		start = 0
		sliding_window_counter = collections.Counter()
		result = 0
		for end in range(len(nums)):
			sliding_window_counter[nums[end]] += 1
			while sliding_window_counter[0] > 1:
				sliding_window_counter[nums[start]] -= 1
				start += 1
			result = max(result, end - start)
		return result


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		l = 0
		r = 0
		zeros = 0
		res = 0
		while r < len(nums):
			if nums[r] == 0:
				zeros += 1
			while zeros > 1:
				if nums[l] == 0:
					zeros -= 1
				l += 1
			res = max(res, r - l)
			r += 1
		return res


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		l = 0
		r = 0
		earliest_one = float('inf')
		earliest_zero = float('inf')
		zeros = 1
		max_len = 0
		while r < len(nums):
			zeros -= nums[r] == 0
			if zeros < 0:
				zeros += nums[l] == 0
				l += 1
			r += 1
		return r - l - 1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		(i, r) = (0, 1)
		for j in range(len(nums)):
			if nums[j] == 0:
				r -= 1
			if r < 0:
				print('yes')
				if nums[i] == 0:
					r += 1
				i += 1
		return j - i


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		w_start = 0
		d = {}
		max_len = 0
		case = 0
		for i in range(0, len(nums)):
			c = str(nums[i])
			if c not in d:
				d[c] = 0
			d[c] += 1
			if str(0) in d:
				while d[str(0)] > 1:
					t = str(nums[w_start])
					d[t] -= 1
					w_start += 1
					case = 1
			max_len = max(max_len, i - w_start + 1 - case)
			case = 0
		return max_len - 1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		prev = 0
		prev_zero = 0
		result = float('-inf')
		boolean = False
		count = 0
		for i in range(len(nums)):
			if nums[i] == 0:
				boolean = True
				count += 1
				if count == 2:
					count -= 1
					prev = prev_zero + 1
				prev_zero = i
			result = max(result, i - prev)
		return result if boolean == True else len(nums) - 1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		if 0 in nums and 1 in nums:
			longest = 0
			i = nums.index(0)
			while True:
				if 0 in nums[:i][::-1]:
					left_side = nums[:i][::-1].index(0)
				else:
					left_side = len(nums[:i][::-1])
				if 0 in nums[i + 1:]:
					right_side = nums[i + 1:].index(0)
				else:
					right_side = len(nums[i + 1:])
				longest = max(left_side + right_side, longest)
				try:
					i = nums[i + 1:].index(0) + i + 1
				except:
					break
			return longest
		elif sum(nums) == 0:
			return 0
		elif sum(nums) == len(nums):
			return len(nums) - 1


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		arr = []
		count = 0
		for i in range(len(nums)):
			if nums[i] == 1:
				count += 1
			elif nums[i] == 0:
				arr.append(count)
				count = 0
		arr.append(count)
		if len(arr) == 1:
			return arr[0] - 1
		maxi = 0
		for j in range(1, len(arr)):
			maxi = max(maxi, arr[j - 1] + arr[j])
		return maxi


class Solution:

	def longestSubarray(self, nums: List[int]) -> int:
		if 0 not in nums:
			return len(nums) - 1
		arr = [0]
		(count, flag) = (0, 0)
		for (idx, num) in enumerate(nums):
			if num == 0:
				if flag == 1:
					arr.append(count)
					count = 0
				arr.append(0)
				flag = 0
			elif num == 1:
				count += 1
				flag = 1
			if idx == len(nums) - 1:
				arr.append(count)
		arr.append(0)
		maxSum = 0
		for i in range(1, len(arr) - 1):
			if arr[i] == 0:
				maxSum = max(maxSum, arr[i - 1] + arr[i + 1])
		return maxSum