import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner a = new Scanner(System.in);		
		long money = a.nextLong();
		long b = 100;
		int num = 0;
		for(long i = b; i <= money; i++) {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		}
		System.out.println(num);
		
	}
} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner a = new Scanner(System.in);		
		long money = a.nextLong();
		long b = 100;
		int num = 0;
		for(long i = b; i <= money; i++) {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		}
		System.out.println(num);
		
	}
} Main public static void main(String[] args) {
		Scanner a = new Scanner(System.in);		
		long money = a.nextLong();
		long b = 100;
		int num = 0;
		for(long i = b; i <= money; i++) {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		}
		System.out.println(num);
		
	} main {
		Scanner a = new Scanner(System.in);		
		long money = a.nextLong();
		long b = 100;
		int num = 0;
		for(long i = b; i <= money; i++) {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		}
		System.out.println(num);
		
	} Scanner a = new Scanner(System.in); a new Scanner(System.in) long money = a.nextLong(); money a.nextLong() a.nextLong a long b = 100; b 100 int num = 0; num 0 for(long i = b; i <= money; i++) {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		} long i = b; long i = b; i b i <= money i money i++ i++ i {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		} {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		} long risi = b / 100; risi b / 100 b 100 b = b + risi b b + risi b risi i = b i b num++ num System.out.println(num) System.out.println System.out System System.out num String[] args args public class Main {

	public static void main(String[] args) {
		Scanner a = new Scanner(System.in);		
		long money = a.nextLong();
		long b = 100;
		int num = 0;
		for(long i = b; i <= money; i++) {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		}
		System.out.println(num);
		
	}
} public class Main {

	public static void main(String[] args) {
		Scanner a = new Scanner(System.in);		
		long money = a.nextLong();
		long b = 100;
		int num = 0;
		for(long i = b; i <= money; i++) {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		}
		System.out.println(num);
		
	}
} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner a = new Scanner(System.in);		
		long money = a.nextLong();
		long b = 100;
		int num = 0;
		for(long i = b; i <= money; i++) {
			long risi = b / 100;
			b = b + risi;
			i = b;
			num++;

		}
		System.out.println(num);
		
	}
}