//B
import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String xs = sc.next();
      	long x = Long.parseLong(xs);
		long count = 100;
		int max = 10000000;
		
		for (int i = 0; i < max; i++) {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		}
	}
} import java.util.*; util.* java public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String xs = sc.next();
      	long x = Long.parseLong(xs);
		long count = 100;
		int max = 10000000;
		
		for (int i = 0; i < max; i++) {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		}
	}
} Main public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String xs = sc.next();
      	long x = Long.parseLong(xs);
		long count = 100;
		int max = 10000000;
		
		for (int i = 0; i < max; i++) {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		}
	} main {
		Scanner sc = new Scanner(System.in);
		String xs = sc.next();
      	long x = Long.parseLong(xs);
		long count = 100;
		int max = 10000000;
		
		for (int i = 0; i < max; i++) {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		}
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String xs = sc.next(); xs sc.next() sc.next sc long x = Long.parseLong(xs); x Long.parseLong(xs) Long.parseLong Long xs long count = 100; count 100 int max = 10000000; max 10000000 for (int i = 0; i < max; i++) {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		} int i = 0; int i = 0; i 0 i < max i max i++ i++ i {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		} {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		} count = (long)((double)count * 1.01) count (long)((double)count * 1.01) (double)count 1.01 if (count >= x) {
				System.out.println(i + 1);
				break;
			} count >= x count x {
				System.out.println(i + 1);
				break;
			} System.out.println(i + 1) System.out.println System.out System System.out i + 1 i 1 break; String[] args args public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String xs = sc.next();
      	long x = Long.parseLong(xs);
		long count = 100;
		int max = 10000000;
		
		for (int i = 0; i < max; i++) {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		}
	}
} public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String xs = sc.next();
      	long x = Long.parseLong(xs);
		long count = 100;
		int max = 10000000;
		
		for (int i = 0; i < max; i++) {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		}
	}
} Main
//B
import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String xs = sc.next();
      	long x = Long.parseLong(xs);
		long count = 100;
		int max = 10000000;
		
		for (int i = 0; i < max; i++) {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		}
	}
}