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

int main(){
	int n;
	cin >> n;
	int ans = 1;
	int count = 0;
	for(int i = 1; i <= n; i++){
		if(ans >= n){
			cout << count << endl;
			break;
		}else{
			ans *= 2;
			count++;
		}
	}
}