import java.util.Scanner;
public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long X = sc.nextLong();
    long a = 100;
    long b = 0;
    //long b = 1;
    //long max = (int)Math.pow(10,18);
    long cnt = 0;

    for(int i=0; i<X; i++) {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    }
    System.out.println(cnt);
  }
} 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 a = 100;
    long b = 0;
    //long b = 1;
    //long max = (int)Math.pow(10,18);
    long cnt = 0;

    for(int i=0; i<X; i++) {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    }
    System.out.println(cnt);
  }
} Main public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long X = sc.nextLong();
    long a = 100;
    long b = 0;
    //long b = 1;
    //long max = (int)Math.pow(10,18);
    long cnt = 0;

    for(int i=0; i<X; i++) {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    }
    System.out.println(cnt);
  } main {
    Scanner sc = new Scanner(System.in);
    long X = sc.nextLong();
    long a = 100;
    long b = 0;
    //long b = 1;
    //long max = (int)Math.pow(10,18);
    long cnt = 0;

    for(int i=0; i<X; i++) {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    }
    System.out.println(cnt);
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long X = sc.nextLong(); X sc.nextLong() sc.nextLong sc long a = 100; a 100 long b = 0; b 0 long cnt = 0; cnt 0 for(int i=0; i<X; i++) {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    } int i=0; int i=0; i 0 i<X i X i++ i++ i {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    } {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    } a+=a/100 a a/100 a 100 b=a b a cnt++ cnt if(b>=X){
        break;
      } b>=X b X {
        break;
      } break; if(X<100){
        continue;
      } X<100 X 100 {
        continue;
      } continue; System.out.println(cnt) System.out.println System.out System System.out cnt String[] args args public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long X = sc.nextLong();
    long a = 100;
    long b = 0;
    //long b = 1;
    //long max = (int)Math.pow(10,18);
    long cnt = 0;

    for(int i=0; i<X; i++) {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    }
    System.out.println(cnt);
  }
} public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long X = sc.nextLong();
    long a = 100;
    long b = 0;
    //long b = 1;
    //long max = (int)Math.pow(10,18);
    long cnt = 0;

    for(int i=0; i<X; i++) {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    }
    System.out.println(cnt);
  }
} 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 a = 100;
    long b = 0;
    //long b = 1;
    //long max = (int)Math.pow(10,18);
    long cnt = 0;

    for(int i=0; i<X; i++) {
      a+=a/100;
      b=a;
      cnt++;
      if(b>=X){
        break;
      }
      if(X<100){
        continue;
      }
    }
    System.out.println(cnt);
  }
}