# Max Consecutive Ones

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<https://leetcode.com/problems/max-consecutive-ones/>
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In this question we are asked:

> Given a binary array, find the maximum number of consecutive 1s in this array.

```
Input: [1,1,0,1,1,1]
Output: 3
```

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This is a for loop through the array, keeping 2 counters.

For every num in the array, we check to see if it is a 1. If it is, we += 1 to the counter. If it's not, we reset the counter.

Everytime we see a 1, we set the answer to the maximum(current\_answer, count).&#x20;

We then return the answer.

```python
class Solution(object):
    def findMaxConsecutiveOnes(self, nums):
        count = 0
        ans = 0
        for num in nums:
            if num == 1:
                count += 1
                ans = max(ans, count )
            else:
                cnt = 0
        return ans
```

This algorithm is O(n) time. As it touches every item in the array exactly once, and the array can be of size N.

The space complexity is O(n) space.
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Click "Answer" tab to see the answer. Try to do it yourself first!