import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		double x = sc.nextLong();
		double n = 100;
		int i = 0;
		while (x > n) {
			n = n * 1.01;
			n = Math.floor(n);
			i++;
			//System.out.println(n);

		}
		System.out.println(i);

	}

} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		double x = sc.nextLong();
		double n = 100;
		int i = 0;
		while (x > n) {
			n = n * 1.01;
			n = Math.floor(n);
			i++;
			//System.out.println(n);

		}
		System.out.println(i);

	}

} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		double x = sc.nextLong();
		double n = 100;
		int i = 0;
		while (x > n) {
			n = n * 1.01;
			n = Math.floor(n);
			i++;
			//System.out.println(n);

		}
		System.out.println(i);

	} main {
		Scanner sc = new Scanner(System.in);
		double x = sc.nextLong();
		double n = 100;
		int i = 0;
		while (x > n) {
			n = n * 1.01;
			n = Math.floor(n);
			i++;
			//System.out.println(n);

		}
		System.out.println(i);

	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) double x = sc.nextLong(); x sc.nextLong() sc.nextLong sc double n = 100; n 100 int i = 0; i 0 while (x > n) {
			n = n * 1.01;
			n = Math.floor(n);
			i++;
			//System.out.println(n);

		} x > n x n {
			n = n * 1.01;
			n = Math.floor(n);
			i++;
			//System.out.println(n);

		} n = n * 1.01 n n * 1.01 n 1.01 n = Math.floor(n) n Math.floor(n) Math.floor Math n i++ i System.out.println(i) System.out.println System.out System System.out i String[] args args public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		double x = sc.nextLong();
		double n = 100;
		int i = 0;
		while (x > n) {
			n = n * 1.01;
			n = Math.floor(n);
			i++;
			//System.out.println(n);

		}
		System.out.println(i);

	}

} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		double x = sc.nextLong();
		double n = 100;
		int i = 0;
		while (x > n) {
			n = n * 1.01;
			n = Math.floor(n);
			i++;
			//System.out.println(n);

		}
		System.out.println(i);

	}

} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		double x = sc.nextLong();
		double n = 100;
		int i = 0;
		while (x > n) {
			n = n * 1.01;
			n = Math.floor(n);
			i++;
			//System.out.println(n);

		}
		System.out.println(i);

	}

}
