import java.util.*;

public class Main {
    public static void main(String[] args){
      Scanner scan = new Scanner(System.in);
      double str = Double.parseDouble((String)scan.next());
      int count=0;
      double total=100;
      
      while(true){
          total *= 1.01;
          total = Math.floor(total);
          count++;
          if(str <= total){
              break;
          }
      }
      
      System.out.println(count);
      scan.close();
    }
}
/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