import java.util.Scanner;
public class Main {
 
	public static void main(String[] args) {
		  Scanner sc = new Scanner(System.in);
          Long n = sc.nextLong();
    Long money = 100L;
    int y = 0;
    while(money < n){
      money += money/100;
      y++;
    }
    System.out.println(y);
    }
}
/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