#include <iostream>
#include <string>
#include <vector>
#include <algorithm>

using namespace std;
typedef long long ll;

int main(){
	ios_base::sync_with_stdio(false);
	ll n;
	cin >> n;
	if(n == 0){
		cout << 0 << endl;
	}else{
		cout << (64 - __builtin_clzll(n)) << endl;
	}
	return 0;
}