import java.util.Scanner;
import java.util.Arrays;

public class Main{
public static void main(String[] args){
Scanner scan=new Scanner(System.in);
long x=scan.nextLong();

int i=0;
long n=100;
while(n<x){
    n=n+n/100;
    i=i+1;
}

System.out.println(i);


}
}
/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