#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
const int LIM = 1000000;
int V[LIM + 1];
pair<int, int> helper[LIM + 1], A[LIM + 1], B[LIM + 1];
int N;
int cnt(int X){
int l = 0, r = N - 1;
int res = 0;
for(int i = 0; i < N; ++i){
if(2 * helper[i].first <= X){
res++;
}
}
while(l < r){
if(helper[l].first + helper[r].first <= X){
res += r - l;
l++;
}
else{
r--;
}
}
return res;
}
int calc(int L, int R){
return cnt(R) - cnt(L - 1);
}
void solve(){
cin >> N;
for(int i = 0; i < N; ++i){
cin >> V[i];
helper[i] = {V[i] & 1, i};
}
sort(helper, helper + N);
int answer = 0;
for(int j = 0; j < 30; ++j){
if(j > 0){
int p1 = -1, p2 = -1;
for(int i = 0; i < N; ++i){
if(!(V[helper[i].second] >> j & 1)){
A[++p1] = {helper[i].first, helper[i].second};
}
else{
B[++p2] = {helper[i].first + (1 << j), helper[i].second};
}
}
for(int i = 0; i <= p1; ++i){
helper[i] = A[i];
}
for(int i = 0; i <= p2; ++i){
helper[i + p1 + 1] = B[i];
}
}
int total = calc((1 << j), (1 << (j + 1)) - 1) + calc((1 << (j + 1)) + (1 << j), (1 << (j + 2)) - 1);
if(total & 1)answer += (1 << j);
}
cout << answer << "\n";
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int tc = 1; //cin >> tc;
while(tc--){
solve();
}
return 0;
}
