Given a set of numbers from 1 to N, each number is exactly present twice so there are N pairs. In the worst-case scenario, how many numbers X should be picked and removed from the set until we find a matching pair?
Example 1:
Input:
N = 1
Output:
2
Explanation:
When N=1 Then there is
one pair and a matching
pair can be extracted in
2 Draws.
Example 2:
Input:
N = 2
Output:
3
Explanation:
When N=2 then there are
2 pairs, let them be {1,2,1,2}
and a matching pair will
be made in 3 draws.
Your Task:
You don't need to read input or print anything. Your task is to complete the function find() which takes an integer N as input parameter and returns an integer, the number of x must be picked and removed from set to find a matching pair.

Expected Time Complexity: O(1)
Expected Space Complexity: O(1)

Constraints:
0 <= N <= 10^{5}

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