# Leetcode: Max Consecutive Ones III

Max Consecutive Ones III Similar Problems:

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

Github: code.dennyzhang.com

Credits To: leetcode.com

Leave me comments, if you have better ways to solve.

• Solution:
```// Blog link: https://code.dennyzhang.com/max-consecutive-ones-iii
// Basic Ideas: slidewindow
//
// Window: max 0 can't be more than K
//
// Think why the result is j-i, instead of j-i+1
//
// Complexity: Time O(n), Space O(1)
func longestOnes(A []int, K int) int {
i, j := 0, 0
for ; j<len(A); j++ {
if A[j] == 0 { K-- }
if K<0 {
if A[i] == 0 { K++ }
i++
}
}
return j-i
}
```

Share It, If You Like It.