import java.util.Scanner;

public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long target = sc.nextLong();
        double mon = 100.0d;
        for(int i = 0;;i++){
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        }
    }
}
/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