import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        long X = scan.nextLong();
      	int year;
        double rate=0.01;
        long money=100;
          for(year=0; money < X; year++){
      			money += Math.floor((double)money*rate);
    	}
		
		System.out.println(year);
			
		}
    } import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        long X = scan.nextLong();
      	int year;
        double rate=0.01;
        long money=100;
          for(year=0; money < X; year++){
      			money += Math.floor((double)money*rate);
    	}
		
		System.out.println(year);
			
		}
    } Main public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        long X = scan.nextLong();
      	int year;
        double rate=0.01;
        long money=100;
          for(year=0; money < X; year++){
      			money += Math.floor((double)money*rate);
    	}
		
		System.out.println(year);
			
		} main {
        Scanner scan = new Scanner(System.in);
        long X = scan.nextLong();
      	int year;
        double rate=0.01;
        long money=100;
          for(year=0; money < X; year++){
      			money += Math.floor((double)money*rate);
    	}
		
		System.out.println(year);
			
		} Scanner scan = new Scanner(System.in); scan new Scanner(System.in) long X = scan.nextLong(); X scan.nextLong() scan.nextLong scan int year; year double rate=0.01; rate 0.01 long money=100; money 100 for(year=0; money < X; year++){
      			money += Math.floor((double)money*rate);
    	} year=0; year=0 year 0 money < X money X year++ year++ year {
      			money += Math.floor((double)money*rate);
    	} {
      			money += Math.floor((double)money*rate);
    	} money += Math.floor((double)money*rate) money Math.floor((double)money*rate) Math.floor Math (double)money*rate (double)money rate System.out.println(year) System.out.println System.out System System.out year String[] args args public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        long X = scan.nextLong();
      	int year;
        double rate=0.01;
        long money=100;
          for(year=0; money < X; year++){
      			money += Math.floor((double)money*rate);
    	}
		
		System.out.println(year);
			
		}
    } public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        long X = scan.nextLong();
      	int year;
        double rate=0.01;
        long money=100;
          for(year=0; money < X; year++){
      			money += Math.floor((double)money*rate);
    	}
		
		System.out.println(year);
			
		}
    } Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        long X = scan.nextLong();
      	int year;
        double rate=0.01;
        long money=100;
          for(year=0; money < X; year++){
      			money += Math.floor((double)money*rate);
    	}
		
		System.out.println(year);
			
		}
    }