import java.util.*;
import java.util.ArrayDeque;
import java.util.Queue;
import java.math.RoundingMode;
import java.math.BigDecimal;
 
 
 
public class Main{
	 public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long count = 0;
		long money = 100;
		while(money<x) {
			money=money+money/100;
			count++;
		}
		System.out.println(count);
	 }
} import java.util.*; util.* java import java.util.ArrayDeque; ArrayDeque java.util import java.util.Queue; Queue java.util import java.math.RoundingMode; RoundingMode java.math import java.math.BigDecimal; BigDecimal java.math public class Main{
	 public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long count = 0;
		long money = 100;
		while(money<x) {
			money=money+money/100;
			count++;
		}
		System.out.println(count);
	 }
} Main public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long count = 0;
		long money = 100;
		while(money<x) {
			money=money+money/100;
			count++;
		}
		System.out.println(count);
	 } main {
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long count = 0;
		long money = 100;
		while(money<x) {
			money=money+money/100;
			count++;
		}
		System.out.println(count);
	 } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long x = sc.nextLong(); x sc.nextLong() sc.nextLong sc long count = 0; count 0 long money = 100; money 100 while(money<x) {
			money=money+money/100;
			count++;
		} money<x money x {
			money=money+money/100;
			count++;
		} money=money+money/100 money money+money/100 money money/100 money 100 count++ count System.out.println(count) System.out.println System.out System System.out count String[] args args public class Main{
	 public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long count = 0;
		long money = 100;
		while(money<x) {
			money=money+money/100;
			count++;
		}
		System.out.println(count);
	 }
} public class Main{
	 public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long count = 0;
		long money = 100;
		while(money<x) {
			money=money+money/100;
			count++;
		}
		System.out.println(count);
	 }
} Main
import java.util.*;
import java.util.ArrayDeque;
import java.util.Queue;
import java.math.RoundingMode;
import java.math.BigDecimal;
 
 
 
public class Main{
	 public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long count = 0;
		long money = 100;
		while(money<x) {
			money=money+money/100;
			count++;
		}
		System.out.println(count);
	 }
}