import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long x = sc.nextLong();
        long start = 100;
        int answer = 0;
        while (x > start) {
            start += start / 100;
            answer++;
        }
        System.out.println(answer);
        sc.close();
    }

} import java.util.Scanner; Scanner java.util public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long x = sc.nextLong();
        long start = 100;
        int answer = 0;
        while (x > start) {
            start += start / 100;
            answer++;
        }
        System.out.println(answer);
        sc.close();
    }

} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long x = sc.nextLong();
        long start = 100;
        int answer = 0;
        while (x > start) {
            start += start / 100;
            answer++;
        }
        System.out.println(answer);
        sc.close();
    } main {
        Scanner sc = new Scanner(System.in);
        long x = sc.nextLong();
        long start = 100;
        int answer = 0;
        while (x > start) {
            start += start / 100;
            answer++;
        }
        System.out.println(answer);
        sc.close();
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long x = sc.nextLong(); x sc.nextLong() sc.nextLong sc long start = 100; start 100 int answer = 0; answer 0 while (x > start) {
            start += start / 100;
            answer++;
        } x > start x start {
            start += start / 100;
            answer++;
        } start += start / 100 start start / 100 start 100 answer++ answer System.out.println(answer) System.out.println System.out System System.out answer sc.close() sc.close sc String[] args args public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long x = sc.nextLong();
        long start = 100;
        int answer = 0;
        while (x > start) {
            start += start / 100;
            answer++;
        }
        System.out.println(answer);
        sc.close();
    }

} public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long x = sc.nextLong();
        long start = 100;
        int answer = 0;
        while (x > start) {
            start += start / 100;
            answer++;
        }
        System.out.println(answer);
        sc.close();
    }

} Main
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long x = sc.nextLong();
        long start = 100;
        int answer = 0;
        while (x > start) {
            start += start / 100;
            answer++;
        }
        System.out.println(answer);
        sc.close();
    }

}
