#include <bits/stdc++.h>
using namespace std;
class Solver {
 public:
  void input() {
    cin >> n;
    a.resize(n);
    for (int i = 0; i < n; i++) {
      cin >> a[i];
    }
  }
  void print() { cout << solve() << endl; }

 private:
  vector<int> a;
  int n;
  long long f(int x) {
    long long ans = 0;
    for (int i = 0; i < n; i++) {
      int j = lower_bound(a.begin(), a.end(), x - a[i]) - a.begin();
      if (i < j) {
        ans += j - i - 1;
      } else {
        break;
      }
    }
    return ans;
  }
  int solve() {
    int ans = 0;
    for (int i = 30; i >= 0; i--) {
      for (int j = 0; j < n; j++) {
        a[j] = (a[j] & ((1 << (i + 1)) - 1));
      }
      sort(a.begin(), a.end());
      long long cur = f(1 << (i + 1)) - f(1 << i);
      cur += f(1 << (i + 2)) - f((1 << i) + (1 << (i + 1)));
      if (cur & 1) {
        ans = (ans | (1 << i));
      }
    }
    return ans;
  }
};
int main() {
  ios::sync_with_stdio(false);
  Solver solver;
  solver.input();
  solver.print();
  return 0;
}
