package yukicoder;

import java.util.Scanner;

public class No_047 {
public static void main(String[] args) {
	Scanner sc = new Scanner(System.in);
	int N = sc.nextInt();
	int b = 1;
	int ans = 0;
	while(b * 2 <= N){
		b *= 2;
		ans++;
	}
	if(b != N){
		ans++;
	}
System.out.println(ans);
}
}