TwoNonRepeatingElement.cpp

// C++ program for above approach
#include <bits/stdc++.h>
using namespace std;

/* This function sets the values of
*x and *y to non-repeating elements
in an array arr[] of size n*/
void get2NonRepeatingNos(int arr[], int n, int* x, int* y)
{
	/* Will hold Xor of all elements */
	int Xor = arr[0];

	/* Will have only single set bit of Xor */
	int set_bit_no;
	int i;
	*x = 0;
	*y = 0;

	/* Get the Xor of all elements */
	for (i = 1; i < n; i++)
		Xor ^= arr[i];

	set_bit_no = Xor & ~(Xor - 1);

	for (i = 0; i < n; i++) {

		if (arr[i] & set_bit_no)
			*x = *x ^ arr[i];
		else {
			*y = *y ^ arr[i];
		}
	}
}

int main()
{
	int arr[] = { 2, 3, 7, 9, 11, 2, 3, 11 };
	int n = sizeof(arr) / sizeof(*arr);
	int* x = new int[(sizeof(int))];
	int* y = new int[(sizeof(int))];
	get2NonRepeatingNos(arr, n, x, y);
	cout << "The non-repeating elements are " << *x
		<< " and " << *y;
}