import java.util.Scanner;
class Main{
  public static void main (String[] args){
    Scanner stdIn = new Scanner(System.in);
    
    long  X = stdIn.nextLong();
    
    int y = 0;
    double money = 100;
    do{
      double r =Math.floor(money * 0.01);
      money = money + r;
      y++;
    }while(money < X);
    System.out.println(y);
  }
} import java.util.Scanner; Scanner java.util class Main{
  public static void main (String[] args){
    Scanner stdIn = new Scanner(System.in);
    
    long  X = stdIn.nextLong();
    
    int y = 0;
    double money = 100;
    do{
      double r =Math.floor(money * 0.01);
      money = money + r;
      y++;
    }while(money < X);
    System.out.println(y);
  }
} Main public static void main (String[] args){
    Scanner stdIn = new Scanner(System.in);
    
    long  X = stdIn.nextLong();
    
    int y = 0;
    double money = 100;
    do{
      double r =Math.floor(money * 0.01);
      money = money + r;
      y++;
    }while(money < X);
    System.out.println(y);
  } main {
    Scanner stdIn = new Scanner(System.in);
    
    long  X = stdIn.nextLong();
    
    int y = 0;
    double money = 100;
    do{
      double r =Math.floor(money * 0.01);
      money = money + r;
      y++;
    }while(money < X);
    System.out.println(y);
  } Scanner stdIn = new Scanner(System.in); stdIn new Scanner(System.in) long  X = stdIn.nextLong(); X stdIn.nextLong() stdIn.nextLong stdIn int y = 0; y 0 double money = 100; money 100 do{
      double r =Math.floor(money * 0.01);
      money = money + r;
      y++;
    }while(money < X); money < X money X {
      double r =Math.floor(money * 0.01);
      money = money + r;
      y++;
    } double r =Math.floor(money * 0.01); r Math.floor(money * 0.01) Math.floor Math money * 0.01 money 0.01 money = money + r money money + r money r y++ y System.out.println(y) System.out.println System.out System System.out y String[] args args
import java.util.Scanner;
class Main{
  public static void main (String[] args){
    Scanner stdIn = new Scanner(System.in);
    
    long  X = stdIn.nextLong();
    
    int y = 0;
    double money = 100;
    do{
      double r =Math.floor(money * 0.01);
      money = money + r;
      y++;
    }while(money < X);
    System.out.println(y);
  }
}
