Max Consecutive Ones

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

Question

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

Answer

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).

We then return the answer.

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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