#include <bits/stdc++.h>
using namespace std;
using lli = long long;
void solve() {
int n; cin >> n;
vector <int> v(n);
for (int i = 0; i < n; ++i) cin >> v[i];
vector <int> vv(n);
lli ans = 0;
for (int b = 0; b < 30; ++b) {
for (int i = 0; i < n; ++i) {
vv[i] = v[i] % (1 << (b + 1));
}
sort(vv.begin(), vv.end());
//must be between 2^(i + 1) and 2^i
lli cnt = 0;
int high = 1 << (b + 1), low = 1 << b;
for (int i = 0; i < n; ++i) {
int ub = lower_bound(vv.begin() + i, vv.end(), high - vv[i]) - vv.begin();
int lb = lower_bound(vv.begin() + i, vv.end(), low - vv[i]) - vv.begin();
cnt += ub - lb;
}
high = (1 << (b + 2)), low = (1 << (b + 1)) + (1 << b);
for (int i = 0; i < n; ++i) {
int ub = lower_bound(vv.begin() + i, vv.end(), high - vv[i]) - vv.begin();
int lb = lower_bound(vv.begin() + i, vv.end(), low - vv[i]) - vv.begin();
cnt += ub - lb;
}
if (cnt & 1) ans |= 1 << b;
}
cout << ans << '\n';
}
int main() {
std::cin.tie(0)->sync_with_stdio(0);
#ifdef LOCAL
auto begin = std::chrono::high_resolution_clock::now();
#endif
int tt = 1;
while (tt--) {
solve();
}
#ifdef LOCAL
auto end = std::chrono::high_resolution_clock::now();
auto elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
std::cerr << "Time measured: " << elapsed.count() * 1e-9 << " seconds.\n";
#endif
return 0;
}
