import java.util.Scanner;
class Bisuketto{
	public static void main(String args[]){
		Scanner s = new Scanner(System.in);
		int N = s.nextInt();
		int num = 0;
		int i = 0;
		while(true){
			num = (int)Math.pow(2 , i);
			if(num >= N){
				System.out.println(i);
				break;
			}
			i++;
		}
	}
}