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