#include <bits/stdc++.h>

using namespace std;

typedef pair<int, int> pii;
typedef long long ll;
const int N = 2000086, MOD = 998244353, INF = 0x3f3f3f3f;
int n, m, w[N];


ll h[N];
int main() {
    cin >> n;
    for (int i = 1; i < n + 1; i++) scanf("%lld", h + i);
    sort(h + 1, h + n + 1);
    set<ll, greater<ll> > l;
    ll sum = 0, ans = 0;
    for (ll i = 1; i < (1ll << 62); i <<= 1) l.insert(i), sum += i;
    for (int i = 1; i < n + 1; i++) {
        if (sum >= h[i]) {
            ll t = sum;
            for (auto u = l.begin(); u != l.end() && h[i] > 0; ) {
                t -= *u;
                if (*u <= h[i]) {
                    h[i] -= *u;
                    sum -= *u;
                    u = l.erase(u);
                } else if (t < h[i]) {
                    h[i] -= *u;
                    sum -= *u;
                    u = l.erase(u);
                } else u++;
            }
        } else ans++;
    }
    if (ans) printf("%lld\n", ans + 62);
    else {
        for (ll i = (1ll << 61), t = 62; i >= 1; i >>= 1, t--)
            if (!l.count(i)) {
                printf("%d\n", t);
                return 0;
            }
    }
    return 0;
}