Given an array of integers of size N find minimum xor of any 2 elements.

Example 1:

Input:
N = 3
arr[] = {9,5,3}
Output: 6
Explanation: 
There are 3 pairs -
9^5 = 12
5^3 = 6
9^3 = 10
Therefore output is 6.

Your Task:
You don't need to read input or print anything. Your task is to complete the function minxorpair() which takes the array arr[], its size N as input parameters and returns the minimum value of xor of any 2 elements.

Expected Time Complexity: O(N)
Expected Auxiliary Space: O(N)

Constraints:
1 <= N <= 10⁵
1<= arr[i] <= 10⁵