import java.util.Scanner;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long yoki = 100;
    for (int i = 1; i <= 3765; i++){
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    }
  }
} 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 yoki = 100;
    for (int i = 1; i <= 3765; i++){
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    }
  }
} Main public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long yoki = 100;
    for (int i = 1; i <= 3765; i++){
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    }
  } main {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long yoki = 100;
    for (int i = 1; i <= 3765; i++){
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    }
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long x = sc.nextLong(); x sc.nextLong() sc.nextLong sc long yoki = 100; yoki 100 for (int i = 1; i <= 3765; i++){
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    } int i = 1; int i = 1; i 1 i <= 3765 i 3765 i++ i++ i {
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    } {
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    } yoki = yoki + yoki / 100 yoki yoki + yoki / 100 yoki yoki / 100 yoki 100 if (yoki >= x) {
        System.out.println(i);
        return;
      } yoki >= x yoki x {
        System.out.println(i);
        return;
      } System.out.println(i) System.out.println System.out System System.out i return; String[] args args public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long yoki = 100;
    for (int i = 1; i <= 3765; i++){
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    }
  }
} public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long yoki = 100;
    for (int i = 1; i <= 3765; i++){
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    }
  }
} 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 yoki = 100;
    for (int i = 1; i <= 3765; i++){
      yoki = yoki + yoki / 100;
      if (yoki >= x) {
        System.out.println(i);
        return;
      }
    }
  }
}
