import java.io.*;
import java.util.*;

public class Main {
        public static void main(String[] args) {
                Scanner scan = new Scanner(System.in);

                long X = scan.nextLong();

                long ganpon = 100;

                long year = 0;

                while (ganpon < X) {
                        year++;
                        ganpon *= 1.01;
                }

                System.out.println(year);
        }

} import java.io.*; io.* java import java.util.*; util.* java public class Main {
        public static void main(String[] args) {
                Scanner scan = new Scanner(System.in);

                long X = scan.nextLong();

                long ganpon = 100;

                long year = 0;

                while (ganpon < X) {
                        year++;
                        ganpon *= 1.01;
                }

                System.out.println(year);
        }

} Main public static void main(String[] args) {
                Scanner scan = new Scanner(System.in);

                long X = scan.nextLong();

                long ganpon = 100;

                long year = 0;

                while (ganpon < X) {
                        year++;
                        ganpon *= 1.01;
                }

                System.out.println(year);
        } main {
                Scanner scan = new Scanner(System.in);

                long X = scan.nextLong();

                long ganpon = 100;

                long year = 0;

                while (ganpon < X) {
                        year++;
                        ganpon *= 1.01;
                }

                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 long ganpon = 100; ganpon 100 long year = 0; year 0 while (ganpon < X) {
                        year++;
                        ganpon *= 1.01;
                } ganpon < X ganpon X {
                        year++;
                        ganpon *= 1.01;
                } year++ year ganpon *= 1.01 ganpon 1.01 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();

                long ganpon = 100;

                long year = 0;

                while (ganpon < X) {
                        year++;
                        ganpon *= 1.01;
                }

                System.out.println(year);
        }

} public class Main {
        public static void main(String[] args) {
                Scanner scan = new Scanner(System.in);

                long X = scan.nextLong();

                long ganpon = 100;

                long year = 0;

                while (ganpon < X) {
                        year++;
                        ganpon *= 1.01;
                }

                System.out.println(year);
        }

} Main
import java.io.*;
import java.util.*;

public class Main {
        public static void main(String[] args) {
                Scanner scan = new Scanner(System.in);

                long X = scan.nextLong();

                long ganpon = 100;

                long year = 0;

                while (ganpon < X) {
                        year++;
                        ganpon *= 1.01;
                }

                System.out.println(year);
        }

}