import java.util.*;
import java.math.*;

public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long d = 100;
    int count = 0;

    while (true) {
      if (d >= x) {
        System.out.println(count);
        break;
      }
      d += d*0.01;
      count++;
    }

  }

} import java.util.*; util.* java import java.math.*; math.* java public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long d = 100;
    int count = 0;

    while (true) {
      if (d >= x) {
        System.out.println(count);
        break;
      }
      d += d*0.01;
      count++;
    }

  }

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

    long d = 100;
    int count = 0;

    while (true) {
      if (d >= x) {
        System.out.println(count);
        break;
      }
      d += d*0.01;
      count++;
    }

  } main {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long d = 100;
    int count = 0;

    while (true) {
      if (d >= x) {
        System.out.println(count);
        break;
      }
      d += d*0.01;
      count++;
    }

  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long x = sc.nextLong(); x sc.nextLong() sc.nextLong sc long d = 100; d 100 int count = 0; count 0 while (true) {
      if (d >= x) {
        System.out.println(count);
        break;
      }
      d += d*0.01;
      count++;
    } true {
      if (d >= x) {
        System.out.println(count);
        break;
      }
      d += d*0.01;
      count++;
    } if (d >= x) {
        System.out.println(count);
        break;
      } d >= x d x {
        System.out.println(count);
        break;
      } System.out.println(count) System.out.println System.out System System.out count break; d += d*0.01 d d*0.01 d 0.01 count++ count String[] args args public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long d = 100;
    int count = 0;

    while (true) {
      if (d >= x) {
        System.out.println(count);
        break;
      }
      d += d*0.01;
      count++;
    }

  }

} public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long d = 100;
    int count = 0;

    while (true) {
      if (d >= x) {
        System.out.println(count);
        break;
      }
      d += d*0.01;
      count++;
    }

  }

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

public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();

    long d = 100;
    int count = 0;

    while (true) {
      if (d >= x) {
        System.out.println(count);
        break;
      }
      d += d*0.01;
      count++;
    }

  }

}
