import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String x = sc.next();
        long X = Long.parseLong(x);
        long sum = 100;
        for(int i = 1; i <= 4000; i++){
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        }  
    }
} import java.util.*; util.* java public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String x = sc.next();
        long X = Long.parseLong(x);
        long sum = 100;
        for(int i = 1; i <= 4000; i++){
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        }  
    }
} Main public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String x = sc.next();
        long X = Long.parseLong(x);
        long sum = 100;
        for(int i = 1; i <= 4000; i++){
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        }  
    } main {
		Scanner sc = new Scanner(System.in);
		String x = sc.next();
        long X = Long.parseLong(x);
        long sum = 100;
        for(int i = 1; i <= 4000; i++){
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        }  
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String x = sc.next(); x sc.next() sc.next sc long X = Long.parseLong(x); X Long.parseLong(x) Long.parseLong Long x long sum = 100; sum 100 for(int i = 1; i <= 4000; i++){
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        } int i = 1; int i = 1; i 1 i <= 4000 i 4000 i++ i++ i {
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        } {
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        } sum = sum + (long)(sum * 0.01) sum sum + (long)(sum * 0.01) sum (long)(sum * 0.01) sum 0.01 if(sum >= X){
            System.out.println(i);
            break;
          } sum >= X sum X {
            System.out.println(i);
            break;
          } System.out.println(i) System.out.println System.out System System.out i break; String[] args args public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String x = sc.next();
        long X = Long.parseLong(x);
        long sum = 100;
        for(int i = 1; i <= 4000; i++){
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        }  
    }
} public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String x = sc.next();
        long X = Long.parseLong(x);
        long sum = 100;
        for(int i = 1; i <= 4000; i++){
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        }  
    }
} Main
import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String x = sc.next();
        long X = Long.parseLong(x);
        long sum = 100;
        for(int i = 1; i <= 4000; i++){
          sum = sum + (long)(sum * 0.01);
          if(sum >= X){
            System.out.println(i);
            break;
          }
        }  
    }
}