import java.util.*;
public class Main  {
   public static void main(String[] args)  {
      Scanner sc = new Scanner(System.in);
      
      long x = sc.nextLong();
      
      long a = 100;
      long count = 0;
      
      while (a < x) {
         a = a + a * 1 / 100;
         count++;
      }
      
      System.out.println(count);
   }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz