import java.util.*;

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