Grokking 228

class Solution {
    public int longestOnes(int[] nums, int k) {
        int ans = 0; // longest window's length
        int left = 0, right = 0; // start-end position of the window
        int zeros = 0; // number of zeros inside the window
        while(right < nums.length) {
            if (nums[right] == 0) zeros++;
            if (zeros > k) {
                if (nums[left] == 0) zeros--;
                ans = Math.max(ans, right - left);
                left++;
            }
            right++;
        }

        return Math.max(ans, right - left);
    }
}