import java.util.Scanner;
public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		long X;
		X = sc.nextLong();
		int i=0;
		long p=100;
			while(p<X) {
				p*=1.01;
				i++;
			}
		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);

		long X;
		X = sc.nextLong();
		int i=0;
		long p=100;
			while(p<X) {
				p*=1.01;
				i++;
			}
		System.out.println(i);
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		long X;
		X = sc.nextLong();
		int i=0;
		long p=100;
			while(p<X) {
				p*=1.01;
				i++;
			}
		System.out.println(i);
	} main {
		Scanner sc = new Scanner(System.in);

		long X;
		X = sc.nextLong();
		int i=0;
		long p=100;
			while(p<X) {
				p*=1.01;
				i++;
			}
		System.out.println(i);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long X; X X = sc.nextLong() X sc.nextLong() sc.nextLong sc int i=0; i 0 long p=100; p 100 while(p<X) {
				p*=1.01;
				i++;
			} p<X p X {
				p*=1.01;
				i++;
			} p*=1.01 p 1.01 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);

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

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

		long X;
		X = sc.nextLong();
		int i=0;
		long p=100;
			while(p<X) {
				p*=1.01;
				i++;
			}
		System.out.println(i);
	}
}