import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        String[] lines = getStdin();
        String str = lines[0];
        long num = Long.parseLong(str);
        long sum = 100;
        int count = 0;

        while (sum < num){
            sum = sum + (sum * 1 / 100);
            count++;
        }
        System.out.println(count);
             
    }
  
  private static String[] getStdin() {
    Scanner scanner = new Scanner(System.in);
    ArrayList<String> lines = new ArrayList<>();
    while (scanner.hasNext()) {
      lines.add(scanner.nextLine());
    }
    return lines.toArray(new String[lines.size()]);
  }
  
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) throws Exception {
        String[] lines = getStdin();
        String str = lines[0];
        long num = Long.parseLong(str);
        long sum = 100;
        int count = 0;

        while (sum < num){
            sum = sum + (sum * 1 / 100);
            count++;
        }
        System.out.println(count);
             
    }
  
  private static String[] getStdin() {
    Scanner scanner = new Scanner(System.in);
    ArrayList<String> lines = new ArrayList<>();
    while (scanner.hasNext()) {
      lines.add(scanner.nextLine());
    }
    return lines.toArray(new String[lines.size()]);
  }
  
} Main public static void main(String[] args) throws Exception {
        String[] lines = getStdin();
        String str = lines[0];
        long num = Long.parseLong(str);
        long sum = 100;
        int count = 0;

        while (sum < num){
            sum = sum + (sum * 1 / 100);
            count++;
        }
        System.out.println(count);
             
    } main {
        String[] lines = getStdin();
        String str = lines[0];
        long num = Long.parseLong(str);
        long sum = 100;
        int count = 0;

        while (sum < num){
            sum = sum + (sum * 1 / 100);
            count++;
        }
        System.out.println(count);
             
    } String[] lines = getStdin(); lines getStdin() getStdin String str = lines[0]; str lines[0] lines 0 long num = Long.parseLong(str); num Long.parseLong(str) Long.parseLong Long str long sum = 100; sum 100 int count = 0; count 0 while (sum < num){
            sum = sum + (sum * 1 / 100);
            count++;
        } sum < num sum num {
            sum = sum + (sum * 1 / 100);
            count++;
        } sum = sum + (sum * 1 / 100) sum sum + (sum * 1 / 100) sum (sum * 1 / 100) sum * 1 sum 1 100 count++ count System.out.println(count) System.out.println System.out System System.out count String[] args args private static String[] getStdin() {
    Scanner scanner = new Scanner(System.in);
    ArrayList<String> lines = new ArrayList<>();
    while (scanner.hasNext()) {
      lines.add(scanner.nextLine());
    }
    return lines.toArray(new String[lines.size()]);
  } getStdin {
    Scanner scanner = new Scanner(System.in);
    ArrayList<String> lines = new ArrayList<>();
    while (scanner.hasNext()) {
      lines.add(scanner.nextLine());
    }
    return lines.toArray(new String[lines.size()]);
  } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) ArrayList<String> lines = new ArrayList<>(); lines new ArrayList<>() while (scanner.hasNext()) {
      lines.add(scanner.nextLine());
    } scanner.hasNext() scanner.hasNext scanner {
      lines.add(scanner.nextLine());
    } lines.add(scanner.nextLine()) lines.add lines scanner.nextLine() scanner.nextLine scanner return lines.toArray(new String[lines.size()]); lines.toArray(new String[lines.size()]) lines.toArray lines new String[lines.size()] lines.size() lines.size lines public class Main {
    public static void main(String[] args) throws Exception {
        String[] lines = getStdin();
        String str = lines[0];
        long num = Long.parseLong(str);
        long sum = 100;
        int count = 0;

        while (sum < num){
            sum = sum + (sum * 1 / 100);
            count++;
        }
        System.out.println(count);
             
    }
  
  private static String[] getStdin() {
    Scanner scanner = new Scanner(System.in);
    ArrayList<String> lines = new ArrayList<>();
    while (scanner.hasNext()) {
      lines.add(scanner.nextLine());
    }
    return lines.toArray(new String[lines.size()]);
  }
  
} public class Main {
    public static void main(String[] args) throws Exception {
        String[] lines = getStdin();
        String str = lines[0];
        long num = Long.parseLong(str);
        long sum = 100;
        int count = 0;

        while (sum < num){
            sum = sum + (sum * 1 / 100);
            count++;
        }
        System.out.println(count);
             
    }
  
  private static String[] getStdin() {
    Scanner scanner = new Scanner(System.in);
    ArrayList<String> lines = new ArrayList<>();
    while (scanner.hasNext()) {
      lines.add(scanner.nextLine());
    }
    return lines.toArray(new String[lines.size()]);
  }
  
} Main
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        String[] lines = getStdin();
        String str = lines[0];
        long num = Long.parseLong(str);
        long sum = 100;
        int count = 0;

        while (sum < num){
            sum = sum + (sum * 1 / 100);
            count++;
        }
        System.out.println(count);
             
    }
  
  private static String[] getStdin() {
    Scanner scanner = new Scanner(System.in);
    ArrayList<String> lines = new ArrayList<>();
    while (scanner.hasNext()) {
      lines.add(scanner.nextLine());
    }
    return lines.toArray(new String[lines.size()]);
  }
  
}
