
import java.io.PrintWriter;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        long x = in.nextLong();
        long start = 100;
        int days = 0;
        while (start + start / 100l <= x) {
            start += start / 100l;
            days++;
        }
        if (start < x) {
            days++;
        }
        out.println(days);
        out.close();
    }
} import java.io.PrintWriter; PrintWriter java.io import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        long x = in.nextLong();
        long start = 100;
        int days = 0;
        while (start + start / 100l <= x) {
            start += start / 100l;
            days++;
        }
        if (start < x) {
            days++;
        }
        out.println(days);
        out.close();
    }
} Main public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        long x = in.nextLong();
        long start = 100;
        int days = 0;
        while (start + start / 100l <= x) {
            start += start / 100l;
            days++;
        }
        if (start < x) {
            days++;
        }
        out.println(days);
        out.close();
    } main {
        Scanner in = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        long x = in.nextLong();
        long start = 100;
        int days = 0;
        while (start + start / 100l <= x) {
            start += start / 100l;
            days++;
        }
        if (start < x) {
            days++;
        }
        out.println(days);
        out.close();
    } Scanner in = new Scanner(System.in); in new Scanner(System.in) PrintWriter out = new PrintWriter(System.out); out new PrintWriter(System.out) long x = in.nextLong(); x in.nextLong() in.nextLong in long start = 100; start 100 int days = 0; days 0 while (start + start / 100l <= x) {
            start += start / 100l;
            days++;
        } start + start / 100l <= x start + start / 100l start start / 100l start 100l x {
            start += start / 100l;
            days++;
        } start += start / 100l start start / 100l start 100l days++ days if (start < x) {
            days++;
        } start < x start x {
            days++;
        } days++ days out.println(days) out.println out days out.close() out.close out String[] args args public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        long x = in.nextLong();
        long start = 100;
        int days = 0;
        while (start + start / 100l <= x) {
            start += start / 100l;
            days++;
        }
        if (start < x) {
            days++;
        }
        out.println(days);
        out.close();
    }
} public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        long x = in.nextLong();
        long start = 100;
        int days = 0;
        while (start + start / 100l <= x) {
            start += start / 100l;
            days++;
        }
        if (start < x) {
            days++;
        }
        out.println(days);
        out.close();
    }
} Main

import java.io.PrintWriter;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        long x = in.nextLong();
        long start = 100;
        int days = 0;
        while (start + start / 100l <= x) {
            start += start / 100l;
            days++;
        }
        if (start < x) {
            days++;
        }
        out.println(days);
        out.close();
    }
}
