Given an array
arr of positive integers sorted in a strictly increasing order, and an integer
kth positive integer that is missing from this array.
Input: arr = [2,3,4,7,11], k = 5 Output: 9 Explanation: The missing positive integers are [1,5,6,8,9,10,12,13,...]. The 5th missing positive integer is 9.
Input: arr = [1,2,3,4], k = 2 Output: 6 Explanation: The missing positive integers are [5,6,7,...]. The 2nd missing positive integer is 6.
1 <= arr.length <= 1000
1 <= arr[i] <= 1000
1 <= k <= 1000
arr[i] < arr[j]for
1 <= i < j <= arr.length
Could you solve this problem in less than O(n) complexity?