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### by Sumit Chourasia | Sep 27, 2020 | Category :coding | Tags : algorithmarrayडेटा-संरचनाआसानleetcode

#### Kth Missing Positive Number - Array - Easy - LeetCode - मिनी टीवी

Given an array arr of positive integers sorted in a strictly increasing order, and an integer k.

Find the kth positive integer that is missing from this array.

Example 1:

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.
Example 2:

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.

Constraints:

1 <= arr.length <= 1000
1 <= arr[i] <= 1000
1 <= k <= 1000
arr[i] < arr[j] for 1 <= i < j <= arr.length

``````public class Solution {
public int FindKthPositive(int[] arr, int k) {
int missing = 0;
int expected = 1;
for(int i=0;i<arr.Length;){
if(arr[i]==expected){
expected++;
i++;
}
else{
missing++;
if(missing==k){
break;
}
expected++;
}

}

if(missing<k){
expected+=k-missing-1;
}
return expected;
}
}``````

Time Complexity: O(n)

Space Complexity: O(1)

Contributed By: Sumit Chourasia
Contributed By: Sumit Chourasia
Contributed By: Sumit Chourasia
Contributed By: Sumit Chourasia