import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ

		Scanner scan = new Scanner(System.in);

		long x = scan.nextLong();

		long deposit = 100L;
		int i =0;

		while(deposit < x) {
			deposit *= 1.01;
			i++;
		}
			System.out.println(i);

			scan.close();

	}

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

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ

		Scanner scan = new Scanner(System.in);

		long x = scan.nextLong();

		long deposit = 100L;
		int i =0;

		while(deposit < x) {
			deposit *= 1.01;
			i++;
		}
			System.out.println(i);

			scan.close();

	}

} Main public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ

		Scanner scan = new Scanner(System.in);

		long x = scan.nextLong();

		long deposit = 100L;
		int i =0;

		while(deposit < x) {
			deposit *= 1.01;
			i++;
		}
			System.out.println(i);

			scan.close();

	} main {
		// TODO 自動生成されたメソッド・スタブ

		Scanner scan = new Scanner(System.in);

		long x = scan.nextLong();

		long deposit = 100L;
		int i =0;

		while(deposit < x) {
			deposit *= 1.01;
			i++;
		}
			System.out.println(i);

			scan.close();

	} Scanner scan = new Scanner(System.in); scan new Scanner(System.in) long x = scan.nextLong(); x scan.nextLong() scan.nextLong scan long deposit = 100L; deposit 100L int i =0; i 0 while(deposit < x) {
			deposit *= 1.01;
			i++;
		} deposit < x deposit x {
			deposit *= 1.01;
			i++;
		} deposit *= 1.01 deposit 1.01 i++ i System.out.println(i) System.out.println System.out System System.out i scan.close() scan.close scan String[] args args public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ

		Scanner scan = new Scanner(System.in);

		long x = scan.nextLong();

		long deposit = 100L;
		int i =0;

		while(deposit < x) {
			deposit *= 1.01;
			i++;
		}
			System.out.println(i);

			scan.close();

	}

} public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ

		Scanner scan = new Scanner(System.in);

		long x = scan.nextLong();

		long deposit = 100L;
		int i =0;

		while(deposit < x) {
			deposit *= 1.01;
			i++;
		}
			System.out.println(i);

			scan.close();

	}

} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ

		Scanner scan = new Scanner(System.in);

		long x = scan.nextLong();

		long deposit = 100L;
		int i =0;

		while(deposit < x) {
			deposit *= 1.01;
			i++;
		}
			System.out.println(i);

			scan.close();

	}

}
