Bitmask_3

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb              push_back
#define mp              make_pair
#define pii             pair<int,int>
#define vi              vector<int>
#define mii             map<int,int>
#define pqb             priority_queue<int>
#define pqs             priority_queue<int,vi,greater<int> >
#define setbits(x)      __builtin_popcountll(x)
#define zrobits(x)      __builtin_ctzll(x)
#define mod 			1000000007
#define tc(t) 			int t;cin >> t;while(t--)
#define for0(i , n)		for(int i=0;i<n;i++)
#define loop(i , a, b)	for(int i=a;i<=b;i++)
#define endl 			'\n'
#define inf 			1e18
#define fi 				first
#define se 				second

int XX[8] = { +1, +1, +1, 0, 0, -1, -1, -1};
int YY[8] = { +1, 0, -1, +1, -1, +1, 0, -1};
int dx[4] = { -1, 1, 0, 0};
int dy[4] = {0, 0, 1, -1};


/*
	Que: We are given an array containg n numbers. All the numbers are present
	thrice except for one number which is only present once. Find the unique number.
	Only use - bitwise operators, and no extra space.

	7
	1 1 1 2 2 2 3
*/

signed main() {

	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);

#ifndef ONLINE_JUDGE
	freopen("input.txt" , "r" , stdin);
	freopen("output.txt" , "w" , stdout);
#endif

	int n;
	cin >> n;

	int count[64] = {0}, no;

	for0(i, n) {
		cin >> no;
		int j = 0;
		while (no) {
			count[j] += (no & 1);
			no >>= 1;
			j++;
		}
	}

	int p = 1, ans = 0;
	for (int i = 0; i < 64; i++) {
		count[i] %= 3;
		ans += count[i] * p;
		p <<= 1;
	}

	cout << ans << endl;

	return 0;
}