import java.math.BigDecimal;
import java.sql.Array;
import java.util.*;
public class Main {
	public static void main(String[] args){
      	
		Scanner sc = new Scanner(System.in);
		
		BigDecimal bd1 = new BigDecimal(sc.next());
		BigDecimal bd  = new BigDecimal("100");
		BigDecimal bd2 = new BigDecimal("1.01");
		for (int i = 1; i < 10000; i++) {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		}
		sc.close();
    }	
		
} import java.math.BigDecimal; BigDecimal java.math import java.sql.Array; Array java.sql import java.util.*; util.* java public class Main {
	public static void main(String[] args){
      	
		Scanner sc = new Scanner(System.in);
		
		BigDecimal bd1 = new BigDecimal(sc.next());
		BigDecimal bd  = new BigDecimal("100");
		BigDecimal bd2 = new BigDecimal("1.01");
		for (int i = 1; i < 10000; i++) {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		}
		sc.close();
    }	
		
} Main public static void main(String[] args){
      	
		Scanner sc = new Scanner(System.in);
		
		BigDecimal bd1 = new BigDecimal(sc.next());
		BigDecimal bd  = new BigDecimal("100");
		BigDecimal bd2 = new BigDecimal("1.01");
		for (int i = 1; i < 10000; i++) {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		}
		sc.close();
    } main {
      	
		Scanner sc = new Scanner(System.in);
		
		BigDecimal bd1 = new BigDecimal(sc.next());
		BigDecimal bd  = new BigDecimal("100");
		BigDecimal bd2 = new BigDecimal("1.01");
		for (int i = 1; i < 10000; i++) {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		}
		sc.close();
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) BigDecimal bd1 = new BigDecimal(sc.next()); bd1 new BigDecimal(sc.next()) BigDecimal bd  = new BigDecimal("100"); bd new BigDecimal("100") BigDecimal bd2 = new BigDecimal("1.01"); bd2 new BigDecimal("1.01") for (int i = 1; i < 10000; i++) {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		} int i = 1; int i = 1; i 1 i < 10000 i 10000 i++ i++ i {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		} {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		} bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN) bd bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN) bd.multiply(bd2).setScale bd.multiply(bd2) bd.multiply bd bd2 0 BigDecimal.ROUND_DOWN BigDecimal BigDecimal.ROUND_DOWN if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			} bd.compareTo(bd1)==1||bd.compareTo(bd1)==0 bd.compareTo(bd1)==1 bd.compareTo(bd1) bd.compareTo bd bd1 1 bd.compareTo(bd1)==0 bd.compareTo(bd1) bd.compareTo bd bd1 0 {
				System.out.println(i);
				break;
			} System.out.println(i) System.out.println System.out System System.out i break; sc.close() sc.close sc String[] args args public class Main {
	public static void main(String[] args){
      	
		Scanner sc = new Scanner(System.in);
		
		BigDecimal bd1 = new BigDecimal(sc.next());
		BigDecimal bd  = new BigDecimal("100");
		BigDecimal bd2 = new BigDecimal("1.01");
		for (int i = 1; i < 10000; i++) {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		}
		sc.close();
    }	
		
} public class Main {
	public static void main(String[] args){
      	
		Scanner sc = new Scanner(System.in);
		
		BigDecimal bd1 = new BigDecimal(sc.next());
		BigDecimal bd  = new BigDecimal("100");
		BigDecimal bd2 = new BigDecimal("1.01");
		for (int i = 1; i < 10000; i++) {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		}
		sc.close();
    }	
		
} Main
import java.math.BigDecimal;
import java.sql.Array;
import java.util.*;
public class Main {
	public static void main(String[] args){
      	
		Scanner sc = new Scanner(System.in);
		
		BigDecimal bd1 = new BigDecimal(sc.next());
		BigDecimal bd  = new BigDecimal("100");
		BigDecimal bd2 = new BigDecimal("1.01");
		for (int i = 1; i < 10000; i++) {
			bd = bd.multiply(bd2).setScale(0, BigDecimal.ROUND_DOWN);
			if (bd.compareTo(bd1)==1||bd.compareTo(bd1)==0) {
				System.out.println(i);
				break;
			}	
		}
		sc.close();
    }	
		
}