XOR to ALL

#include <bits/stdc++.h>
// #include <atcoder/all>
using namespace std;
#define int long long
#define all(x) (x).begin(), (x).end()
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pair<int, int>> vpi;
typedef pair<int, int> pi;
#define f first
#define s second
#define pb push_back
#define endl "\n"
#define yes cout << "YES" << endl
#define no cout << "NO" << endl
#define init(x, a) memset(x, a, sizeof(x))
const int mod1 = 1e9 + 7, mod2 = 998244353, INF = 2e18, N = 2e5 + 5, L = 19;
int gcd(int a, int b) { return b == 0 ? a : gcd(b, a % b); }
// -----------------------------------------------------------------------------

void solve()
{
    int n;
    cin >> n;
    vi a(n);
    int sum = 0;
    vi ones(31), zeros(31);
    for (int i = 0; i < n; i++)
    {
        cin >> a[i];
        sum += a[i];
    }
    for (int b = 0; b < 31; b++)
    {
        int num1 = 0, num2 = 0;
        for (int i = 0; i < n; i++)
        {
            if ((a[i] >> b) & 1)
            {
                num1++;
            }
            else
            {
                num2++;
            }
        }
        ones[b] = num1, zeros[b] = num2;
    }
    // cout << ones[0] + zeros[0] << endl;
    for (int i = 0; i < n; i++)
    {
        int temp = 0;
        for (int b = 0; b < 31; b++)
        {
            if ((a[i] >> b) & 1)
            {
                // zeros to ones
                temp += (1LL << b) * zeros[b];
            }
            else
            {
                // if zero, add the ones
                temp += (1LL << b) * ones[b];
            }
        }
        sum = max(sum, temp);
    }
    cout << sum << endl;
    return;
}

signed main()
{
    // __START__;
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int t = 1;
    // cin >> t;
    while (t--)
    {
        solve();
    }
    // __END__;
    return 0;
}