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

int main() {

int n;
cin>>n;
int count=0;
int sum=1;
for (int i = 0; ; ++i) {
	if(n<=sum){
		cout<<count<<endl;
		return 0;
	}
	sum=sum*2;
	count++;
}
}