import java.util.Scanner;
public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long x,ans=0,mon=100;
		x = sc.nextLong();
		while(mon<x) {
			mon+=mon*0.01;
			ans++;
		}
	System.out.println(ans);
	}
} import java.util.Scanner; Scanner java.util public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long x,ans=0,mon=100;
		x = sc.nextLong();
		while(mon<x) {
			mon+=mon*0.01;
			ans++;
		}
	System.out.println(ans);
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long x,ans=0,mon=100;
		x = sc.nextLong();
		while(mon<x) {
			mon+=mon*0.01;
			ans++;
		}
	System.out.println(ans);
	} main {
		Scanner sc = new Scanner(System.in);
		long x,ans=0,mon=100;
		x = sc.nextLong();
		while(mon<x) {
			mon+=mon*0.01;
			ans++;
		}
	System.out.println(ans);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long x x ans=0 ans 0 mon=100; mon 100 x = sc.nextLong() x sc.nextLong() sc.nextLong sc while(mon<x) {
			mon+=mon*0.01;
			ans++;
		} mon<x mon x {
			mon+=mon*0.01;
			ans++;
		} mon+=mon*0.01 mon mon*0.01 mon 0.01 ans++ ans System.out.println(ans) System.out.println System.out System System.out ans String[] args args public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long x,ans=0,mon=100;
		x = sc.nextLong();
		while(mon<x) {
			mon+=mon*0.01;
			ans++;
		}
	System.out.println(ans);
	}
} public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long x,ans=0,mon=100;
		x = sc.nextLong();
		while(mon<x) {
			mon+=mon*0.01;
			ans++;
		}
	System.out.println(ans);
	}
} Main
import java.util.Scanner;
public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long x,ans=0,mon=100;
		x = sc.nextLong();
		while(mon<x) {
			mon+=mon*0.01;
			ans++;
		}
	System.out.println(ans);
	}
}