import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner s = new Scanner(System.in);
        final long RISHI = s.nextLong();
        // int yokin = 100;
        double d_yokin = 100.0;
        int year = 0;

        while (d_yokin < RISHI) {
            d_yokin = Math.floor(d_yokin * 1.01);
            year++;
        }
        System.out.println(year);
  }
}
/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