import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

class Main {
    public static void main(final String[] args) throws Exception {

        try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in));) {
            long N = Long.parseLong(br.readLine());
            long condition = 90000000000000000L;
            long ans = 0;
            long base = 100;
            if (condition < N) {
                N = N / 10000000000000L;
                base = condition / 10000000000000L;
                ans = 3517;
            }
            while (base < N) {
                base = (base * 100 + (base * 1)) / 100;
                ans++;
            }

            System.out.println(ans);
        } catch (IOException | NumberFormatException e) {
            e.printStackTrace();
            System.exit(0);
        } catch (final Exception e) {
            e.printStackTrace();
            System.exit(0);
        }
    }
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io class Main {
    public static void main(final String[] args) throws Exception {

        try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in));) {
            long N = Long.parseLong(br.readLine());
            long condition = 90000000000000000L;
            long ans = 0;
            long base = 100;
            if (condition < N) {
                N = N / 10000000000000L;
                base = condition / 10000000000000L;
                ans = 3517;
            }
            while (base < N) {
                base = (base * 100 + (base * 1)) / 100;
                ans++;
            }

            System.out.println(ans);
        } catch (IOException | NumberFormatException e) {
            e.printStackTrace();
            System.exit(0);
        } catch (final Exception e) {
            e.printStackTrace();
            System.exit(0);
        }
    }
} Main public static void main(final String[] args) throws Exception {

        try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in));) {
            long N = Long.parseLong(br.readLine());
            long condition = 90000000000000000L;
            long ans = 0;
            long base = 100;
            if (condition < N) {
                N = N / 10000000000000L;
                base = condition / 10000000000000L;
                ans = 3517;
            }
            while (base < N) {
                base = (base * 100 + (base * 1)) / 100;
                ans++;
            }

            System.out.println(ans);
        } catch (IOException | NumberFormatException e) {
            e.printStackTrace();
            System.exit(0);
        } catch (final Exception e) {
            e.printStackTrace();
            System.exit(0);
        }
    } main {

        try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in));) {
            long N = Long.parseLong(br.readLine());
            long condition = 90000000000000000L;
            long ans = 0;
            long base = 100;
            if (condition < N) {
                N = N / 10000000000000L;
                base = condition / 10000000000000L;
                ans = 3517;
            }
            while (base < N) {
                base = (base * 100 + (base * 1)) / 100;
                ans++;
            }

            System.out.println(ans);
        } catch (IOException | NumberFormatException e) {
            e.printStackTrace();
            System.exit(0);
        } catch (final Exception e) {
            e.printStackTrace();
            System.exit(0);
        }
    } try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in));) {
            long N = Long.parseLong(br.readLine());
            long condition = 90000000000000000L;
            long ans = 0;
            long base = 100;
            if (condition < N) {
                N = N / 10000000000000L;
                base = condition / 10000000000000L;
                ans = 3517;
            }
            while (base < N) {
                base = (base * 100 + (base * 1)) / 100;
                ans++;
            }

            System.out.println(ans);
        } catch (IOException | NumberFormatException e) {
            e.printStackTrace();
            System.exit(0);
        } catch (final Exception e) {
            e.printStackTrace();
            System.exit(0);
        } catch (IOException | NumberFormatException e) {
            e.printStackTrace();
            System.exit(0);
        } IOException | NumberFormatException e {
            e.printStackTrace();
            System.exit(0);
        } e.printStackTrace() e.printStackTrace e System.exit(0) System.exit System 0 catch (final Exception e) {
            e.printStackTrace();
            System.exit(0);
        } final Exception e {
            e.printStackTrace();
            System.exit(0);
        } e.printStackTrace() e.printStackTrace e System.exit(0) System.exit System 0 {
            long N = Long.parseLong(br.readLine());
            long condition = 90000000000000000L;
            long ans = 0;
            long base = 100;
            if (condition < N) {
                N = N / 10000000000000L;
                base = condition / 10000000000000L;
                ans = 3517;
            }
            while (base < N) {
                base = (base * 100 + (base * 1)) / 100;
                ans++;
            }

            System.out.println(ans);
        } BufferedReader br = new BufferedReader(new InputStreamReader(System.in)) BufferedReader br = new BufferedReader(new InputStreamReader(System.in)) new BufferedReader(new InputStreamReader(System.in)) long N = Long.parseLong(br.readLine()); N Long.parseLong(br.readLine()) Long.parseLong Long br.readLine() br.readLine br long condition = 90000000000000000L; condition 90000000000000000L long ans = 0; ans 0 long base = 100; base 100 if (condition < N) {
                N = N / 10000000000000L;
                base = condition / 10000000000000L;
                ans = 3517;
            } condition < N condition N {
                N = N / 10000000000000L;
                base = condition / 10000000000000L;
                ans = 3517;
            } N = N / 10000000000000L N N / 10000000000000L N 10000000000000L base = condition / 10000000000000L base condition / 10000000000000L condition 10000000000000L ans = 3517 ans 3517 while (base < N) {
                base = (base * 100 + (base * 1)) / 100;
                ans++;
            } base < N base N {
                base = (base * 100 + (base * 1)) / 100;
                ans++;
            } base = (base * 100 + (base * 1)) / 100 base (base * 100 + (base * 1)) / 100 (base * 100 + (base * 1)) base * 100 base 100 (base * 1) base 1 100 ans++ ans System.out.println(ans) System.out.println System.out System System.out ans final String[] args args
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

class Main {
    public static void main(final String[] args) throws Exception {

        try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in));) {
            long N = Long.parseLong(br.readLine());
            long condition = 90000000000000000L;
            long ans = 0;
            long base = 100;
            if (condition < N) {
                N = N / 10000000000000L;
                base = condition / 10000000000000L;
                ans = 3517;
            }
            while (base < N) {
                base = (base * 100 + (base * 1)) / 100;
                ans++;
            }

            System.out.println(ans);
        } catch (IOException | NumberFormatException e) {
            e.printStackTrace();
            System.exit(0);
        } catch (final Exception e) {
            e.printStackTrace();
            System.exit(0);
        }
    }
}