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

int main(){
	int N;
	cin >> N;
	vector<long long> H(N);
	for(int i=0;i<N;i++) cin >> H[i];
	sort(H.begin(),H.end());
	cout << *ranges::partition_point(
		views::iota(N,N+61),[&](int x){
			priority_queue<long long> A(H.begin(),H.begin()+min((N+60-x),N));
			for(int i=min(x-1,59);i>=0 && !A.empty();i--){
				long long pos=A.top();
				A.pop();
				if(pos>=(1LL<<i+1)) return true;
				else if(pos>=(1LL<<i)) A.push(pos-(1LL<<i));
			}
			return false;
		}
	) << '\n';
}