import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scn= new Scanner(System.in);
		long  x = scn.nextLong();
		long cur =100;
		int cnt =0;
		while(cur<x){
			cur+=cur*0.01;
			cnt++;
		}

		System.out.println(cnt);
	}

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

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scn= new Scanner(System.in);
		long  x = scn.nextLong();
		long cur =100;
		int cnt =0;
		while(cur<x){
			cur+=cur*0.01;
			cnt++;
		}

		System.out.println(cnt);
	}

} Main public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scn= new Scanner(System.in);
		long  x = scn.nextLong();
		long cur =100;
		int cnt =0;
		while(cur<x){
			cur+=cur*0.01;
			cnt++;
		}

		System.out.println(cnt);
	} main {
		// TODO Auto-generated method stub
		Scanner scn= new Scanner(System.in);
		long  x = scn.nextLong();
		long cur =100;
		int cnt =0;
		while(cur<x){
			cur+=cur*0.01;
			cnt++;
		}

		System.out.println(cnt);
	} Scanner scn= new Scanner(System.in); scn new Scanner(System.in) long  x = scn.nextLong(); x scn.nextLong() scn.nextLong scn long cur =100; cur 100 int cnt =0; cnt 0 while(cur<x){
			cur+=cur*0.01;
			cnt++;
		} cur<x cur x {
			cur+=cur*0.01;
			cnt++;
		} cur+=cur*0.01 cur cur*0.01 cur 0.01 cnt++ cnt System.out.println(cnt) System.out.println System.out System System.out cnt String[] args args public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scn= new Scanner(System.in);
		long  x = scn.nextLong();
		long cur =100;
		int cnt =0;
		while(cur<x){
			cur+=cur*0.01;
			cnt++;
		}

		System.out.println(cnt);
	}

} public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scn= new Scanner(System.in);
		long  x = scn.nextLong();
		long cur =100;
		int cnt =0;
		while(cur<x){
			cur+=cur*0.01;
			cnt++;
		}

		System.out.println(cnt);
	}

} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scn= new Scanner(System.in);
		long  x = scn.nextLong();
		long cur =100;
		int cnt =0;
		while(cur<x){
			cur+=cur*0.01;
			cnt++;
		}

		System.out.println(cnt);
	}

}