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# Max Consecutive Ones II

Given a binary array, find the maximum number of consecutive 1s in this array if you can flip at most one 0.

**Example 1:**

```
Input:
 [1,0,1,1,0]

Output:
 4

Explanation:
 Flip the first zero will get the the maximum number of consecutive 1s.
    After flipping, the maximum number of consecutive 1s is 4.
```

**Note:**

* The input array will only contain

  `0`

  and

  `1`

  .
* The length of input array is a positive integer and will not exceed 10,000

**Follow up:**\
What if the input numbers come in one by one as an**infinite stream**? In other words, you can't store all numbers coming from the stream as it's too large to hold in memory. Could you solve it efficiently?

分析

还是Map思想，不过就2个数，直接判断counter了

```
class Solution:
    def findMaxConsecutiveOnes(self, nums: List[int]) -> int:
        s,e,counter, ll,maxLen=0,0,0, len(nums),0
        while e < ll:
            counter = counter if nums[e] == 1 else counter+1
            e = e+1
            while counter > 1:
                counter = counter if nums[s] == 1 else counter-1
                s = s+1
            maxLen = max(maxLen, e - s)
        return maxLen
```