#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
#define pb push_back
#define in insert
#define lb lower_bound
#define F first
#define S second
#define sz size()
#define all(v) v.begin(),v.end()
#define FOR1(x, n) for(int j = x; j <= n; j ++)
#define FOR(x, n, m, d) for(int x = n; x <= m; x += d)
#define FORR(x, n, m, d) for(int x = n; x >= m; x -= d)
#define nikita ios_base::sync_with_stdio(0), cin.tie(0);
const int N = 1e6+5;
int a[N], b[N], pref[N], dp[N];
int n,m,k,sum=0,x,y, ans, r, cnt, l, mod = 1e9+7, mt[N];
bool used[N];
vector<int>g[N];
string s, str;
map<int, int>mp;
void solve(){
nikita
cin >> n;
ans = 0;
vector<int>v;
int mx = 0;
set<int>st;
FOR(i, 1, n, 1)cin >> a[i], st.in(a[i]);
k = 1;
for(auto i : st)mp[i] = k, k ++;
FOR(i, 1, n, 1){
b[mp[a[i]]]++;
if(b[mp[a[i]]] == 1)v.pb(a[i]);
}
if(n <= 6e3){
ans = 0;
FOR(i, 1, n, 1){
FOR(j, i, n, 1){
ans ^= (a[i] + a[j]);
}
}
cout << ans;
return;
}
FOR(i, 0, v.sz-1, 1){
FOR(j, i, v.sz-1, 1){
if(v[i] == v[j]){
if((b[mp[v[i]]] * (b[mp[v[i]]] - 1) / 2 + b[mp[v[i]]]) % 2)ans ^= (v[i] * 2);
continue;
}
if(b[mp[v[i]]] * b[mp[v[j]]] % 2)ans ^= (v[i] + v[j]);
}
}
cout << ans;
}
signed main(){
nikita
int tt = 1;
if(!tt)cin >> tt;
FOR(i, 1, tt, 1)solve();
}
