1004.max-consecutive-ones-iii.java

/*
 * @lc app=leetcode id=1004 lang=java
 *
 * [1004] Max Consecutive Ones III
 *
 * https://leetcode.com/problems/max-consecutive-ones-iii/description/
 *
 * algorithms
 * Medium (57.10%)
 * Likes:    759
 * Dislikes: 19
 * Total Accepted:    40.5K
 * Total Submissions: 70.9K
 * Testcase Example:  '[1,1,1,0,0,0,1,1,1,1,0]\n2'
 *
 * 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 <= A.length <= 20000
 * 0 <= K <= A.length
 * A[i] is 0 or 1 
 * 
 * 
 * 
 */

// @lc code=start
class Solution {
    public int longestOnes(int[] A, int K) {
        if (A == null || A.length == 0 || K < 0) return 0;

        int n = A.length;
        int i = 0;
        int longest = 0;
        for (int j = 0; j < n; j++) {
            if (A[j] == 0) {
                K--;
                while(K < 0) {
                    if (A[i] == 0) K++;
                    i++;
                }
            }

            longest = Math.max(longest, j - i + 1);
        }

        return longest;
    }
}
// @lc code=end