import java.util.Scanner;
 
public class Main {
 
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    final long x = sc.nextLong();
    long l = 100;
    for(int i=0;;i++){
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    }
  }
} import java.util.Scanner; Scanner java.util public class Main {
 
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    final long x = sc.nextLong();
    long l = 100;
    for(int i=0;;i++){
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    }
  }
} Main public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    final long x = sc.nextLong();
    long l = 100;
    for(int i=0;;i++){
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    }
  } main {
    Scanner sc = new Scanner(System.in);
    final long x = sc.nextLong();
    long l = 100;
    for(int i=0;;i++){
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    }
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) final long x = sc.nextLong(); x sc.nextLong() sc.nextLong sc long l = 100; l 100 for(int i=0;;i++){
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    } int i=0; int i=0; i 0 i++ i++ i {
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    } {
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    } if(l >= x){
        System.out.println(i);
        break;
      } l >= x l x {
        System.out.println(i);
        break;
      } System.out.println(i) System.out.println System.out System System.out i break; l += l / 100 l l / 100 l 100 String[] args args public class Main {
 
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    final long x = sc.nextLong();
    long l = 100;
    for(int i=0;;i++){
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    }
  }
} public class Main {
 
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    final long x = sc.nextLong();
    long l = 100;
    for(int i=0;;i++){
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    }
  }
} Main
import java.util.Scanner;
 
public class Main {
 
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    final long x = sc.nextLong();
    long l = 100;
    for(int i=0;;i++){
      if(l >= x){
        System.out.println(i);
        break;
      }
      l += l / 100;
    }
  }
}