import java.util.Scanner;

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

		long X = scan.nextLong();
		long cnt=0, money=100;

		while(money < X){
			cnt++;
			money += money*0.01;
		}

		System.out.println(cnt);

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

		long X = scan.nextLong();
		long cnt=0, money=100;

		while(money < X){
			cnt++;
			money += money*0.01;
		}

		System.out.println(cnt);

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

		long X = scan.nextLong();
		long cnt=0, money=100;

		while(money < X){
			cnt++;
			money += money*0.01;
		}

		System.out.println(cnt);

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

		long X = scan.nextLong();
		long cnt=0, money=100;

		while(money < X){
			cnt++;
			money += money*0.01;
		}

		System.out.println(cnt);

		scan.close();
	} Scanner scan = new Scanner(System.in); scan new Scanner(System.in) long X = scan.nextLong(); X scan.nextLong() scan.nextLong scan long cnt=0 cnt 0 money=100; money 100 while(money < X){
			cnt++;
			money += money*0.01;
		} money < X money X {
			cnt++;
			money += money*0.01;
		} cnt++ cnt money += money*0.01 money money*0.01 money 0.01 System.out.println(cnt) System.out.println System.out System System.out cnt scan.close() scan.close scan String[] args args public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);

		long X = scan.nextLong();
		long cnt=0, money=100;

		while(money < X){
			cnt++;
			money += money*0.01;
		}

		System.out.println(cnt);

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

		long X = scan.nextLong();
		long cnt=0, money=100;

		while(money < X){
			cnt++;
			money += money*0.01;
		}

		System.out.println(cnt);

		scan.close();
	}
} Main
import java.util.Scanner;

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

		long X = scan.nextLong();
		long cnt=0, money=100;

		while(money < X){
			cnt++;
			money += money*0.01;
		}

		System.out.println(cnt);

		scan.close();
	}
}
