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:

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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:

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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 <= A.length <= 20000
  • 0 <= K <= A.length
  • A[i] is 0 or 1

Solution:

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class Solution {
    public int longestOnes(int[] A, int K) {
        int i = 0;
        int j = 0;
        while (i < A.length) {
            if (A[i] == 0) {
                K--;
            }
            if (K < 0) {
                if (A[j] == 0) {
                    K++;
                }
                j++;
            }
            i++;
        }
        return i - j;
    }
}