import java.lang.Math;
import java.util.Scanner;
class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long n = sc.nextLong();
        double interest = 100;
        int year = 0;
        while (interest < n){  
            year += 1;
            interest *= 1.01;
            interest = Math.floor(interest);
            if (interest >= n){
                break;
            }
        }
        System.out.println(year);
    }
} import java.lang.Math; Math java.lang import java.util.Scanner; Scanner java.util class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long n = sc.nextLong();
        double interest = 100;
        int year = 0;
        while (interest < n){  
            year += 1;
            interest *= 1.01;
            interest = Math.floor(interest);
            if (interest >= n){
                break;
            }
        }
        System.out.println(year);
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long n = sc.nextLong();
        double interest = 100;
        int year = 0;
        while (interest < n){  
            year += 1;
            interest *= 1.01;
            interest = Math.floor(interest);
            if (interest >= n){
                break;
            }
        }
        System.out.println(year);
    } main {
        Scanner sc = new Scanner(System.in);
        long n = sc.nextLong();
        double interest = 100;
        int year = 0;
        while (interest < n){  
            year += 1;
            interest *= 1.01;
            interest = Math.floor(interest);
            if (interest >= n){
                break;
            }
        }
        System.out.println(year);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long n = sc.nextLong(); n sc.nextLong() sc.nextLong sc double interest = 100; interest 100 int year = 0; year 0 while (interest < n){  
            year += 1;
            interest *= 1.01;
            interest = Math.floor(interest);
            if (interest >= n){
                break;
            }
        } interest < n interest n {  
            year += 1;
            interest *= 1.01;
            interest = Math.floor(interest);
            if (interest >= n){
                break;
            }
        } year += 1 year 1 interest *= 1.01 interest 1.01 interest = Math.floor(interest) interest Math.floor(interest) Math.floor Math interest if (interest >= n){
                break;
            } interest >= n interest n {
                break;
            } break; System.out.println(year) System.out.println System.out System System.out year String[] args args
import java.lang.Math;
import java.util.Scanner;
class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long n = sc.nextLong();
        double interest = 100;
        int year = 0;
        while (interest < n){  
            year += 1;
            interest *= 1.01;
            interest = Math.floor(interest);
            if (interest >= n){
                break;
            }
        }
        System.out.println(year);
    }
}
