import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        
        Scanner scanner = new Scanner(System.in);
        long X = scanner.nextLong();
        long A = 100;
        int Y = 0;
        
        while(A<X){
            A *= 1.01;
            Y++;
        }
        
        System.out.println(Y);
        
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) throws Exception {
        
        Scanner scanner = new Scanner(System.in);
        long X = scanner.nextLong();
        long A = 100;
        int Y = 0;
        
        while(A<X){
            A *= 1.01;
            Y++;
        }
        
        System.out.println(Y);
        
    }
} Main public static void main(String[] args) throws Exception {
        
        Scanner scanner = new Scanner(System.in);
        long X = scanner.nextLong();
        long A = 100;
        int Y = 0;
        
        while(A<X){
            A *= 1.01;
            Y++;
        }
        
        System.out.println(Y);
        
    } main {
        
        Scanner scanner = new Scanner(System.in);
        long X = scanner.nextLong();
        long A = 100;
        int Y = 0;
        
        while(A<X){
            A *= 1.01;
            Y++;
        }
        
        System.out.println(Y);
        
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) long X = scanner.nextLong(); X scanner.nextLong() scanner.nextLong scanner long A = 100; A 100 int Y = 0; Y 0 while(A<X){
            A *= 1.01;
            Y++;
        } A<X A X {
            A *= 1.01;
            Y++;
        } A *= 1.01 A 1.01 Y++ Y System.out.println(Y) System.out.println System.out System System.out Y String[] args args public class Main {
    public static void main(String[] args) throws Exception {
        
        Scanner scanner = new Scanner(System.in);
        long X = scanner.nextLong();
        long A = 100;
        int Y = 0;
        
        while(A<X){
            A *= 1.01;
            Y++;
        }
        
        System.out.println(Y);
        
    }
} public class Main {
    public static void main(String[] args) throws Exception {
        
        Scanner scanner = new Scanner(System.in);
        long X = scanner.nextLong();
        long A = 100;
        int Y = 0;
        
        while(A<X){
            A *= 1.01;
            Y++;
        }
        
        System.out.println(Y);
        
    }
} Main
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        
        Scanner scanner = new Scanner(System.in);
        long X = scanner.nextLong();
        long A = 100;
        int Y = 0;
        
        while(A<X){
            A *= 1.01;
            Y++;
        }
        
        System.out.println(Y);
        
    }
}
