import java.util.*;

public class Main{
      public static void main(String[] args) {
            Scanner sc = new Scanner(System.in);
            long X = sc.nextLong();
            long goal = 100;
            int count = 0;
        	double av = 0;
            while(goal < X){
              	av = goal / 100;
                goal = goal + (long)(av);
                count++;
            }
            System.out.println(count);
          }
} import java.util.*; util.* java public class Main{
      public static void main(String[] args) {
            Scanner sc = new Scanner(System.in);
            long X = sc.nextLong();
            long goal = 100;
            int count = 0;
        	double av = 0;
            while(goal < X){
              	av = goal / 100;
                goal = goal + (long)(av);
                count++;
            }
            System.out.println(count);
          }
} Main public static void main(String[] args) {
            Scanner sc = new Scanner(System.in);
            long X = sc.nextLong();
            long goal = 100;
            int count = 0;
        	double av = 0;
            while(goal < X){
              	av = goal / 100;
                goal = goal + (long)(av);
                count++;
            }
            System.out.println(count);
          } main {
            Scanner sc = new Scanner(System.in);
            long X = sc.nextLong();
            long goal = 100;
            int count = 0;
        	double av = 0;
            while(goal < X){
              	av = goal / 100;
                goal = goal + (long)(av);
                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 goal = 100; goal 100 int count = 0; count 0 double av = 0; av 0 while(goal < X){
              	av = goal / 100;
                goal = goal + (long)(av);
                count++;
            } goal < X goal X {
              	av = goal / 100;
                goal = goal + (long)(av);
                count++;
            } av = goal / 100 av goal / 100 goal 100 goal = goal + (long)(av) goal goal + (long)(av) goal (long)(av) 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 goal = 100;
            int count = 0;
        	double av = 0;
            while(goal < X){
              	av = goal / 100;
                goal = goal + (long)(av);
                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 goal = 100;
            int count = 0;
        	double av = 0;
            while(goal < X){
              	av = goal / 100;
                goal = goal + (long)(av);
                count++;
            }
            System.out.println(count);
          }
} Main
import java.util.*;

public class Main{
      public static void main(String[] args) {
            Scanner sc = new Scanner(System.in);
            long X = sc.nextLong();
            long goal = 100;
            int count = 0;
        	double av = 0;
            while(goal < X){
              	av = goal / 100;
                goal = goal + (long)(av);
                count++;
            }
            System.out.println(count);
          }
}