import java.util.Scanner;

class Main{
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        long x=sc.nextLong();
        long p=100;
        long yr=0;
        long balance=p;
        while(balance<x)
        {
            long temp=balance/100;
            balance+=temp;
            yr++;
        }
        System.out.println(yr);
    }
}
/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