#include <iostream>
#include <algorithm>
#include <cmath>
using namespace std;
long long i, j, n, v[1000001], aux1, aux2, k, w[1000001], st, dr, st2, dr2;
long long sum, mod, mod2, mod3, auxi, cnt, cnt2;
int main()
{
cin >> n;
for ( i = 1; i <= n; i++ ) {
cin >> v[i];
}
for ( k = 30; k >= 0; k-- ) {
auxi = 0;
mod = pow ( 2, k+1 );
mod2 = pow ( 2, k );
for ( i = 1; i <= n; i++ ) {
w[i] = v[i]%mod;
}
sort ( w+1, w+n+1 );
for ( i = 1; i <= n; i++ ) {
st = lower_bound ( w+i, w+n+1, mod2-w[i] )-w;
if ( w[st] >= mod2-w[i] && st <= n && st >= i ) {
dr = lower_bound( w+i, w+n+1, mod-w[i] )-w;
dr--;
if ( dr >= st && w[dr] < mod-w[i] && dr <= n && dr >= i ) {
auxi += (dr-st+1);
}
}
st = lower_bound ( w+i, w+n+1, mod+mod2-w[i] )-w;
if ( w[st] >= mod+mod2-w[i] && st <= n && st >= i ) {
dr = lower_bound ( w+i, w+n+1, mod*2-w[i] )-w;
dr--;
if ( dr >= st && w[dr] < mod*2-w[i] && dr <= n && dr >= i ) {
auxi += (dr-st+1);
}
}
/*if ( w[i]+w[j] >= mod2 && w[i]+w[j] < mod ) {
auxi++;
}
else if ( w[i]+w[j] >= mod+mod2 && w[i]+w[j] < mod*2 ) {
auxi++;
}*/
}
if ( auxi%2 == 1 ) {
sum += mod2;
}
}
cout << sum;
return 0;
}
