Given a binary array, find the maximum number of consecutive 1s in this array.
- The input array will only contain 0 and 1.
- The length of input array is a positive integer and will not exceed 10,000
Input: [1,1,0,1,1,1]
Output: 3
Explanation: The first two digits or the last three digits are consecutive 1s.
The maximum number of consecutive 1s is 3.