import java.util.Scanner;
public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		long x = sc.nextLong();
		long  dep = 100;
		double rate = 1.01;

		for(int i = 1; i <= 4000; i++) {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		}



	}

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

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		long x = sc.nextLong();
		long  dep = 100;
		double rate = 1.01;

		for(int i = 1; i <= 4000; i++) {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		}



	}

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

		long x = sc.nextLong();
		long  dep = 100;
		double rate = 1.01;

		for(int i = 1; i <= 4000; i++) {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		}



	} main {
		Scanner sc = new Scanner(System.in);

		long x = sc.nextLong();
		long  dep = 100;
		double rate = 1.01;

		for(int i = 1; i <= 4000; i++) {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		}



	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long x = sc.nextLong(); x sc.nextLong() sc.nextLong sc long  dep = 100; dep 100 double rate = 1.01; rate 1.01 for(int i = 1; i <= 4000; i++) {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		} int i = 1; int i = 1; i 1 i <= 4000 i 4000 i++ i++ i {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		} {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		} dep *= 1.01 dep 1.01 if(dep >= x) {
				System.out.println(i);
				break;
			} dep >= x dep x {
				System.out.println(i);
				break;
			} System.out.println(i) System.out.println System.out System System.out i break; String[] args args public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		long x = sc.nextLong();
		long  dep = 100;
		double rate = 1.01;

		for(int i = 1; i <= 4000; i++) {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		}



	}

} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		long x = sc.nextLong();
		long  dep = 100;
		double rate = 1.01;

		for(int i = 1; i <= 4000; i++) {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		}



	}

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

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		long x = sc.nextLong();
		long  dep = 100;
		double rate = 1.01;

		for(int i = 1; i <= 4000; i++) {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				break;
			}
		}



	}

}