import java.io.*;
import java.util.*;

public class Main
{
   public static void main(String[] args)
   {
      Scanner in = new Scanner(System.in);

      double firstDay = in.nextInt();
      double goal = in.nextInt();

      double done = firstDay;
      int days = 1;
      while (done <= goal) {
          done += (done / 10) * 7;
          days++;
      }

      System.out.print(days - 1);
   }
}