Two numbers with odd occurrences

Given an unsorted array, arr[] of size N and that contains even number of occurrences for all numbers except two numbers. Find the two numbers in decreasing order which has odd occurrences.

• Time : O(n)
• Space : O(1)

c++

class Solution{
public:
    vector<int> twoOddNum(int Arr[], int N) {
        int mask = 0;
        for(int i = 0; i < N; i++) {
            mask ^= Arr[i];
        }

        mask = mask & ~(mask - 1);

        int xor1 = 0, xor2 = 0;
        for(int i = 0; i < N; i++) {
            if(mask & Arr[i]) xor1 ^= Arr[i];
            else xor2 ^= Arr[i];
        }
        return {max(xor1, xor2), min(xor1, xor2)};
    }
};