package yukiCoder;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class No00047 {

	public static void main(String[] args) {
		BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));

		try {
			long input = Long.parseLong(bufferedReader.readLine());

			int cnt = 0;
			for (int biscuits = 1 ; biscuits < input ; biscuits *= 2) {
				cnt++;
			}
			System.out.println(cnt);
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

}