import java.util.Scanner;
public class Main {
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		long X = Long.parseLong(scan.nextLine());
		long P = 100;
		int cnt = 0;

		for (int i = 0; i < 3800; i++){
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		}
	}
} import java.util.Scanner; Scanner java.util public class Main {
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		long X = Long.parseLong(scan.nextLine());
		long P = 100;
		int cnt = 0;

		for (int i = 0; i < 3800; i++){
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		}
	}
} Main public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		long X = Long.parseLong(scan.nextLine());
		long P = 100;
		int cnt = 0;

		for (int i = 0; i < 3800; i++){
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		}
	} main {
		Scanner scan = new Scanner(System.in);
		long X = Long.parseLong(scan.nextLine());
		long P = 100;
		int cnt = 0;

		for (int i = 0; i < 3800; i++){
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		}
	} Scanner scan = new Scanner(System.in); scan new Scanner(System.in) long X = Long.parseLong(scan.nextLine()); X Long.parseLong(scan.nextLine()) Long.parseLong Long scan.nextLine() scan.nextLine scan long P = 100; P 100 int cnt = 0; cnt 0 for (int i = 0; i < 3800; i++){
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		} int i = 0; int i = 0; i 0 i < 3800 i 3800 i++ i++ i {
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		} {
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		} if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			} X > P X P {
				P += P / 100;
				cnt++;
			} P += P / 100 P P / 100 P 100 cnt++ cnt {
				System.out.println(cnt);
				return;
			} System.out.println(cnt) System.out.println System.out System System.out cnt return; String[] args args public class Main {
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		long X = Long.parseLong(scan.nextLine());
		long P = 100;
		int cnt = 0;

		for (int i = 0; i < 3800; i++){
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		}
	}
} public class Main {
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		long X = Long.parseLong(scan.nextLine());
		long P = 100;
		int cnt = 0;

		for (int i = 0; i < 3800; i++){
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		}
	}
} Main
import java.util.Scanner;
public class Main {
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		long X = Long.parseLong(scan.nextLine());
		long P = 100;
		int cnt = 0;

		for (int i = 0; i < 3800; i++){
			if (X > P){
				P += P / 100;
				cnt++;
			}else {
				System.out.println(cnt);
				return;
			}
		}
	}
}
