import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();
    long ans = 0;
    long yo = 100;
    for(long i = 1; i < Long.MAX_VALUE; i++) {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    }
    System.out.println(ans);
  }
} 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 ans = 0;
    long yo = 100;
    for(long i = 1; i < Long.MAX_VALUE; i++) {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    }
    System.out.println(ans);
  }
} Main public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();
    long ans = 0;
    long yo = 100;
    for(long i = 1; i < Long.MAX_VALUE; i++) {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    }
    System.out.println(ans);
  } main {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();
    long ans = 0;
    long yo = 100;
    for(long i = 1; i < Long.MAX_VALUE; i++) {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    }
    System.out.println(ans);
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long x = sc.nextLong(); x sc.nextLong() sc.nextLong sc long ans = 0; ans 0 long yo = 100; yo 100 for(long i = 1; i < Long.MAX_VALUE; i++) {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    } long i = 1; long i = 1; i 1 i < Long.MAX_VALUE i Long.MAX_VALUE Long Long.MAX_VALUE i++ i++ i {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    } {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    } yo = (yo + (yo / 100)) yo (yo + (yo / 100)) yo (yo / 100) yo 100 if(yo >= x) {
        ans = i;
        break;
      } yo >= x yo x {
        ans = i;
        break;
      } ans = i ans i break; System.out.println(ans) System.out.println System.out System System.out ans String[] args args public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();
    long ans = 0;
    long yo = 100;
    for(long i = 1; i < Long.MAX_VALUE; i++) {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    }
    System.out.println(ans);
  }
} public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();
    long ans = 0;
    long yo = 100;
    for(long i = 1; i < Long.MAX_VALUE; i++) {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    }
    System.out.println(ans);
  }
} Main
import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long x = sc.nextLong();
    long ans = 0;
    long yo = 100;
    for(long i = 1; i < Long.MAX_VALUE; i++) {
      yo = (yo + (yo / 100));
      if(yo >= x) {
        ans = i;
        break;
      }
    }
    System.out.println(ans);
  }
}