/******************************************************************************

                              Online C++ Compiler.
               Code, Compile, Run and Debug C++ program online.
Write your code in this editor and press "Run" button to compile and execute it.

*******************************************************************************/

// C++ program to find the sum of XOR of
// all subarray of the array

#include <iostream>
#include <vector>
using namespace std;

// Function to calculate the sum of XOR
// of all subarrays
int findXorSum(int arr[], int n)
{
	// variable to store
	// the final sum
	int sum = 0;

	// multiplier
	int mul = 1;

	for (int i = 0; i < 30; i++) {

		// variable to store number of
		// sub-arrays with odd number of elements
		// with ith bits starting from the first
		// element to the end of the array
		int c_odd = 0;

		// variable to check the status
		// of the odd-even count while
		// calculating c_odd
		bool odd = 0;

		// loop to calculate initial
		// value of c_odd
		for (int j = 0; j < n; j++) {
			if ((arr[j] & (1 << i)) > 0)
				odd = (!odd);
			if (odd)
				c_odd++;
		}

		// loop to iterate through
		// all the elements of the
		// array and update sum
		for (int j = 0; j < n; j++) {
			sum += (mul * c_odd);

			if ((arr[j] & (1 << i)) > 0)
				c_odd = (n - j - c_odd);
		}

		// updating the multiplier
		mul *= 2;
	}
	
	for (int j = 0; j < n; j++) sum -= arr[j];

	// returning the sum
	return sum;
}

// Driver Code
int main()
{
	//int arr[] = { 1, 3, 2 };
	int arr[] = {2, 5, 6, 5, 2, 1, 7};

	int n = sizeof(arr) / sizeof(arr[0]);

	cout << findXorSum(arr, n);

	return 0;
}