import java.util.*;

public class Main {
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		int n=sc.nextInt();
		int x=1;
		int ans=0;
		if(n==1){System.out.println(0);return;}
		while(true){
			x*=2;
			ans++;
			if(x>=n)break;
		}
		System.out.println(ans);
	}
	}