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

        long X = scan.nextLong();
        int year= 0;
        long money=100;
        while(money<X){
            money= (long) (money*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