import java.util.*;

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