import java.util.Scanner;
public class Main {
 
	public static void main(String[] args) {
		  Scanner sc = new Scanner(System.in);
          Long n = sc.nextLong();
    Long money = 100L;
    int y = 0;
    while(money < n){
      money += money/100;
      y++;
    }
    System.out.println(y);
    }
} import java.util.Scanner; Scanner java.util public class Main {
 
	public static void main(String[] args) {
		  Scanner sc = new Scanner(System.in);
          Long n = sc.nextLong();
    Long money = 100L;
    int y = 0;
    while(money < n){
      money += money/100;
      y++;
    }
    System.out.println(y);
    }
} Main public static void main(String[] args) {
		  Scanner sc = new Scanner(System.in);
          Long n = sc.nextLong();
    Long money = 100L;
    int y = 0;
    while(money < n){
      money += money/100;
      y++;
    }
    System.out.println(y);
    } main {
		  Scanner sc = new Scanner(System.in);
          Long n = sc.nextLong();
    Long money = 100L;
    int y = 0;
    while(money < n){
      money += money/100;
      y++;
    }
    System.out.println(y);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) Long n = sc.nextLong(); n sc.nextLong() sc.nextLong sc Long money = 100L; money 100L int y = 0; y 0 while(money < n){
      money += money/100;
      y++;
    } money < n money n {
      money += money/100;
      y++;
    } money += money/100 money money/100 money 100 y++ y System.out.println(y) System.out.println System.out System System.out y String[] args args public class Main {
 
	public static void main(String[] args) {
		  Scanner sc = new Scanner(System.in);
          Long n = sc.nextLong();
    Long money = 100L;
    int y = 0;
    while(money < n){
      money += money/100;
      y++;
    }
    System.out.println(y);
    }
} public class Main {
 
	public static void main(String[] args) {
		  Scanner sc = new Scanner(System.in);
          Long n = sc.nextLong();
    Long money = 100L;
    int y = 0;
    while(money < n){
      money += money/100;
      y++;
    }
    System.out.println(y);
    }
} Main
import java.util.Scanner;
public class Main {
 
	public static void main(String[] args) {
		  Scanner sc = new Scanner(System.in);
          Long n = sc.nextLong();
    Long money = 100L;
    int y = 0;
    while(money < n){
      money += money/100;
      y++;
    }
    System.out.println(y);
    }
}