import java.io.BufferedReader;
import java.io.*;
import java.util.*;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Collections;

public class Main {
	public static void main(final String[] args){
    
        Scanner sc = new Scanner(System.in);

        long x = sc.nextLong();

        double a = 100;
        long k = 0;
        int count = 0;

        double rate = 1.01;
        
        while(x > a){
            a = rate * a;
            k = (long)a;
            a = (double)k;
            count++;
        }
        System.out.println(count);


        
        






    }
}
/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