import java.util.Scanner;

public class Main {

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

        final long x = sc.nextLong();

        long ans = 0;
        long money = 100;
        while (true) {
            if (money >= x) {
                System.out.println(ans);
                return;
            }

            money += money * 0.01;
            ans++;
        }
    }
} import java.util.Scanner; Scanner java.util public class Main {

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

        final long x = sc.nextLong();

        long ans = 0;
        long money = 100;
        while (true) {
            if (money >= x) {
                System.out.println(ans);
                return;
            }

            money += money * 0.01;
            ans++;
        }
    }
} Main public static void main(String[] args) {
        final Scanner sc = new Scanner(System.in);

        final long x = sc.nextLong();

        long ans = 0;
        long money = 100;
        while (true) {
            if (money >= x) {
                System.out.println(ans);
                return;
            }

            money += money * 0.01;
            ans++;
        }
    } main {
        final Scanner sc = new Scanner(System.in);

        final long x = sc.nextLong();

        long ans = 0;
        long money = 100;
        while (true) {
            if (money >= x) {
                System.out.println(ans);
                return;
            }

            money += money * 0.01;
            ans++;
        }
    } final Scanner sc = new Scanner(System.in); sc new Scanner(System.in) final long x = sc.nextLong(); x sc.nextLong() sc.nextLong sc long ans = 0; ans 0 long money = 100; money 100 while (true) {
            if (money >= x) {
                System.out.println(ans);
                return;
            }

            money += money * 0.01;
            ans++;
        } true {
            if (money >= x) {
                System.out.println(ans);
                return;
            }

            money += money * 0.01;
            ans++;
        } if (money >= x) {
                System.out.println(ans);
                return;
            } money >= x money x {
                System.out.println(ans);
                return;
            } System.out.println(ans) System.out.println System.out System System.out ans return; money += money * 0.01 money money * 0.01 money 0.01 ans++ ans String[] args args public class Main {

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

        final long x = sc.nextLong();

        long ans = 0;
        long money = 100;
        while (true) {
            if (money >= x) {
                System.out.println(ans);
                return;
            }

            money += money * 0.01;
            ans++;
        }
    }
} public class Main {

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

        final long x = sc.nextLong();

        long ans = 0;
        long money = 100;
        while (true) {
            if (money >= x) {
                System.out.println(ans);
                return;
            }

            money += money * 0.01;
            ans++;
        }
    }
} Main
import java.util.Scanner;

public class Main {

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

        final long x = sc.nextLong();

        long ans = 0;
        long money = 100;
        while (true) {
            if (money >= x) {
                System.out.println(ans);
                return;
            }

            money += money * 0.01;
            ans++;
        }
    }
}
