#include <bits/stdc++.h>
#include <iostream>
#define ll long long
using namespace std;


int main(void){
    ll n; cin >> n;
    vector<ll> bbits(65, 0);
    for(ll i = 0; i < n; ++i){
        ll x; cin >> x;
        for(ll j = 0; j < 64; ++j){
            if(x&(1LL<<j)) bbits[j]++;
        }
    }
    ll ans = 0;
    for(ll i = 0; i < 65; ++i){
        if(bbits[i]) ans+=(1LL<<i);
        if(i<64) bbits[i+1] += bbits[i]/2;
    }
    cout << ans << '\n';
    return 0;

}