import java.util.Scanner;
public class Main {
    public static void main(String[] args) throws Exception {
        Scanner stdIn= new Scanner(System.in);
        long x = stdIn.nextLong();
        long a=100;
        int y=0;
        for(;a<x;y++){
            a+=a/100;
        }
        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