import java.util.*;
 
public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        long X = sc.nextLong();
        long m = 100;
        long count=0;
        
        for(int i=1;;i++){
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        }
        System.out.println(count);
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        long X = sc.nextLong();
        long m = 100;
        long count=0;
        
        for(int i=1;;i++){
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        }
        System.out.println(count);
    }
} Main public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        long X = sc.nextLong();
        long m = 100;
        long count=0;
        
        for(int i=1;;i++){
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        }
        System.out.println(count);
    } main {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        long X = sc.nextLong();
        long m = 100;
        long count=0;
        
        for(int i=1;;i++){
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        }
        System.out.println(count);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long X = sc.nextLong(); X sc.nextLong() sc.nextLong sc long m = 100; m 100 long count=0; count 0 for(int i=1;;i++){
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        } int i=1; int i=1; i 1 i++ i++ i {
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        } {
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        } if(m>=X){
                break;
            } m>=X m X {
                break;
            } break; m = m + m/100 m m + m/100 m m/100 m 100 count++ count System.out.println(count) System.out.println System.out System System.out count String[] args args public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        long X = sc.nextLong();
        long m = 100;
        long count=0;
        
        for(int i=1;;i++){
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        }
        System.out.println(count);
    }
} public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        long X = sc.nextLong();
        long m = 100;
        long count=0;
        
        for(int i=1;;i++){
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        }
        System.out.println(count);
    }
} Main
import java.util.*;
 
public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        long X = sc.nextLong();
        long m = 100;
        long count=0;
        
        for(int i=1;;i++){
            if(m>=X){
                break;
            }
            m = m + m/100;
            count++;
        }
        System.out.println(count);
    }
}