import java.util.Scanner;

public class Biscket {

	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		int N = s.nextInt(), count, num = 1;
		s.close();
		for(count = 0;num < N; count++){
			if(num * 2 <= N){
				num *= 2;
			}else{
				num = N;
			}
		}
		System.out.println(count);

	}

}