import java.util.*;

public class Main {

    public static void main(String args[]) {

        // 入力
        Scanner sc = new Scanner(System.in);
        long x = Long.parseLong(sc.next());
        sc.close();

        // 主処理
        long amount = 100;
        int count = 0;
        while (amount < x) {
            amount += amount / 100;
            count++;
        }
        int result = count;

        // 出力
        System.out.println(result);
    }
} import java.util.*; util.* java public class Main {

    public static void main(String args[]) {

        // 入力
        Scanner sc = new Scanner(System.in);
        long x = Long.parseLong(sc.next());
        sc.close();

        // 主処理
        long amount = 100;
        int count = 0;
        while (amount < x) {
            amount += amount / 100;
            count++;
        }
        int result = count;

        // 出力
        System.out.println(result);
    }
} Main public static void main(String args[]) {

        // 入力
        Scanner sc = new Scanner(System.in);
        long x = Long.parseLong(sc.next());
        sc.close();

        // 主処理
        long amount = 100;
        int count = 0;
        while (amount < x) {
            amount += amount / 100;
            count++;
        }
        int result = count;

        // 出力
        System.out.println(result);
    } main {

        // 入力
        Scanner sc = new Scanner(System.in);
        long x = Long.parseLong(sc.next());
        sc.close();

        // 主処理
        long amount = 100;
        int count = 0;
        while (amount < x) {
            amount += amount / 100;
            count++;
        }
        int result = count;

        // 出力
        System.out.println(result);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long x = Long.parseLong(sc.next()); x Long.parseLong(sc.next()) Long.parseLong Long sc.next() sc.next sc sc.close() sc.close sc long amount = 100; amount 100 int count = 0; count 0 while (amount < x) {
            amount += amount / 100;
            count++;
        } amount < x amount x {
            amount += amount / 100;
            count++;
        } amount += amount / 100 amount amount / 100 amount 100 count++ count int result = count; result count System.out.println(result) System.out.println System.out System System.out result String args[] args public class Main {

    public static void main(String args[]) {

        // 入力
        Scanner sc = new Scanner(System.in);
        long x = Long.parseLong(sc.next());
        sc.close();

        // 主処理
        long amount = 100;
        int count = 0;
        while (amount < x) {
            amount += amount / 100;
            count++;
        }
        int result = count;

        // 出力
        System.out.println(result);
    }
} public class Main {

    public static void main(String args[]) {

        // 入力
        Scanner sc = new Scanner(System.in);
        long x = Long.parseLong(sc.next());
        sc.close();

        // 主処理
        long amount = 100;
        int count = 0;
        while (amount < x) {
            amount += amount / 100;
            count++;
        }
        int result = count;

        // 出力
        System.out.println(result);
    }
} Main
import java.util.*;

public class Main {

    public static void main(String args[]) {

        // 入力
        Scanner sc = new Scanner(System.in);
        long x = Long.parseLong(sc.next());
        sc.close();

        // 主処理
        long amount = 100;
        int count = 0;
        while (amount < x) {
            amount += amount / 100;
            count++;
        }
        int result = count;

        // 出力
        System.out.println(result);
    }
}
