import java.util.Scanner;
public class Main {
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		long  X = s.nextLong();
	    long money =100;
		long Xyear =0;
		while( money < X ) {
			money *= 1.01;
			Xyear++;
		}
		System.out.println(Xyear);
	}

} import java.util.Scanner; Scanner java.util public class Main {
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		long  X = s.nextLong();
	    long money =100;
		long Xyear =0;
		while( money < X ) {
			money *= 1.01;
			Xyear++;
		}
		System.out.println(Xyear);
	}

} Main public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		long  X = s.nextLong();
	    long money =100;
		long Xyear =0;
		while( money < X ) {
			money *= 1.01;
			Xyear++;
		}
		System.out.println(Xyear);
	} main {
		Scanner s = new Scanner(System.in);
		long  X = s.nextLong();
	    long money =100;
		long Xyear =0;
		while( money < X ) {
			money *= 1.01;
			Xyear++;
		}
		System.out.println(Xyear);
	} Scanner s = new Scanner(System.in); s new Scanner(System.in) long  X = s.nextLong(); X s.nextLong() s.nextLong s long money =100; money 100 long Xyear =0; Xyear 0 while( money < X ) {
			money *= 1.01;
			Xyear++;
		} money < X money X {
			money *= 1.01;
			Xyear++;
		} money *= 1.01 money 1.01 Xyear++ Xyear System.out.println(Xyear) System.out.println System.out System System.out Xyear String[] args args public class Main {
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		long  X = s.nextLong();
	    long money =100;
		long Xyear =0;
		while( money < X ) {
			money *= 1.01;
			Xyear++;
		}
		System.out.println(Xyear);
	}

} public class Main {
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		long  X = s.nextLong();
	    long money =100;
		long Xyear =0;
		while( money < X ) {
			money *= 1.01;
			Xyear++;
		}
		System.out.println(Xyear);
	}

} Main
import java.util.Scanner;
public class Main {
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		long  X = s.nextLong();
	    long money =100;
		long Xyear =0;
		while( money < X ) {
			money *= 1.01;
			Xyear++;
		}
		System.out.println(Xyear);
	}

}