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

int main() {
	ios::sync_with_stdio(false); cin.tie(nullptr);
	int n;
	ll res=0;
	vector<ll> s(129, 0);
	cin >> n;
	for (ll i =0; i < n; i++) {
		ll var;
		cin >> var;
		for( ll x = 0; var / (1<<x); x++) {
			//cout << var << " " << x << " " << (var & (1<<x) ? 1 : 0)<< "\n";
			s[x] += var & (1<<x) ? 1 : 0;
		}
	}
	int ii = 0;
	while (ii < 128) {
			//cout << ii << " " << s[ii] << "\n";
			if (s[ii])
				res += (1 << ii);
			s[ii+1] += s[ii] /2;
			ii++;
	}
	cout << res << "\n";

    return 0;
}