#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
#include <stdlib.h>
#include <atcoder/all>
using namespace atcoder;
using namespace std;
#define rep(i, a, n) for(ll i = a; i < n; i++)
#define rrep(i, a, n) for(ll i = a; i >= n; i--)
#define inr(l, x, r) (l <= x && x < r)
#define ll long long
#define ld long double
#define pii pair<int, int>
#define pll pair<ll, ll>
#define all(x) (x).begin(), (x).end()
//constexpr ll MOD = 1000000007;
constexpr ll MOD = 998244353;
constexpr int IINF = 1001001001;
constexpr ll INF = 1LL<<60;
template<class t,class u> void chmax(t&a,u b){if(a<b)a=b;}
template<class t,class u> void chmin(t&a,u b){if(b<a)a=b;}

using mint = modint998244353;

ll gcd(ll a, ll b){
    if(a%b == 0){
      return b;
    }else{
      return gcd(b, a%b);
    }
}

ll lcm(ll a, ll b){
    return a*b / gcd(a, b);
}

ll powMod(ll x, ll n, ll mod) {
    if (n == 0) return 1 % mod;
    ll val = powMod(x, n / 2, mod);
    val *= val;
    val %= mod;
    if (n % 2 == 1) val *= x;
    return val % mod;
}

int main() {
    ll n; cin >> n;
    vector<ll> h(n); 
    rep(i,0,n) cin >> h[i];
    sort(h.begin(), h.end(), greater<ll>());
    ll ng = 0, ok = 1e5+30;
    vector<ll> pow2(61,1);
    rep(i,1,61) pow2[i] = pow2[i-1]*2;
    auto f = [&](ll m){
        if(m < n) return false;
        if(m >= n+60) return true;
        priority_queue<ll> pq;
        rep(i,0,n) pq.push(h[i]);
        rrep(i,m-1,0){
            if(pq.empty()) return true;
            ll x = pq.top(); pq.pop();
            ll at = i >= 60 ? INF : pow2[i];
            if(x > at){
                pq.push(x - at);
            }
        }
        return pq.empty();
    };
    while(ok - ng > 1){
        ll mid = (ok + ng) / 2;
        if(f(mid)) ok = mid;
        else ng = mid;
    }
    cout << ok << endl;
    return 0;
}