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