import java.util.Scanner;

public class Run {
    public static void main (String arg[]) {
        Scanner scan = new Scanner(System.in);
        int N = scan.nextInt();
        if (N < 1||N > 100000000) System.exit(1);

        int tap = 0;
        int tmp = 1;
        while (N >= tmp * 2){
            tmp *= 2;
            tap++;
        }
        N -= tmp;
        if (N!=0) tap++;
        System.out.println(tap);
    }
}