import java.util.Scanner;

public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long target = sc.nextLong();
        double mon = 100.0d;
        for(int i = 0;;i++){
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        }
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long target = sc.nextLong();
        double mon = 100.0d;
        for(int i = 0;;i++){
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        }
    }
} Main public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long target = sc.nextLong();
        double mon = 100.0d;
        for(int i = 0;;i++){
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        }
    } main {
        Scanner sc = new Scanner(System.in);
        long target = sc.nextLong();
        double mon = 100.0d;
        for(int i = 0;;i++){
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        }
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long target = sc.nextLong(); target sc.nextLong() sc.nextLong sc double mon = 100.0d; mon 100.0d for(int i = 0;;i++){
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        } int i = 0; int i = 0; i 0 i++ i++ i {
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        } {
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        } if(mon>=target){
                System.out.println(i);
                break;
            } mon>=target mon target {
                System.out.println(i);
                break;
            } System.out.println(i) System.out.println System.out System System.out i break; mon = mon*1.01d mon mon*1.01d mon 1.01d mon = Math.floor(mon) mon Math.floor(mon) Math.floor Math mon String[] args args public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long target = sc.nextLong();
        double mon = 100.0d;
        for(int i = 0;;i++){
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        }
    }
} public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long target = sc.nextLong();
        double mon = 100.0d;
        for(int i = 0;;i++){
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        }
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        long target = sc.nextLong();
        double mon = 100.0d;
        for(int i = 0;;i++){
            if(mon>=target){
                System.out.println(i);
                break;
            }
            mon = mon*1.01d;
            mon = Math.floor(mon);
        }
    }
}