Max Consecutive Ones III

Given an array A of 0s and 1s, we may change up to K values from 0 to 1.

Return the length of the longest (contiguous) subarray that contains only 1s.

Example 1:

Input: A = [1,1,1,0,0,0,1,1,1,1,0], K = 2
Output: 6
Explanation: 
[1,1,1,0,0,1,1,1,1,1,1]
Bolded numbers were flipped from 0 to 1.  The longest subarray is underlined.

Example 2:

Input: A = [0,0,1,1,0,0,1,1,1,0,1,1,0,0,0,1,1,1,1], K = 3
Output: 10
Explanation: 
[0,0,1,1,1,1,1,1,1,1,1,1,0,0,0,1,1,1,1]
Bolded numbers were flipped from 0 to 1.  The longest subarray is underlined.

Note:

1. 1 <= A.length <= 20000

2. 0 <= K <= A.length

3. A[i] is 0 or 1

class Solution {
    public int longestOnes(int[] A, int K) {
        int zerosUsed = 0, max = 0;
        int start = 0, end = 0;
        while (end < A.length) {
            if (A[end] == 0)
                zerosUsed++;
            while (zerosUsed > K) {
                if (A[start] == 0)
                    zerosUsed--;
                start++;
            }
            max = Math.max(max, end - start + 1);
            end++;
        }
        return max;
    }
}