import java.util.*;
import java.io.*;

public class Main {
    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in), 32768);
    static PrintWriter out = new PrintWriter(System.out);
    static StringTokenizer t;

    static String sn() {
        while (t == null || !t.hasMoreTokens()) {
            try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            }
        }
        return t.nextToken();
    }

    static int ni() {
        return Integer.parseInt(sn());
    }

    static long nlo() {
        return Long.parseLong(sn());
    }

    public static void main(String args[]) {
        int t = 1;//ni();
        while (t-- > 0) {
            solve();
        }
        out.close();
    }

    static long mod = (long) 1e9 + 7;

    static long pro(long a, long b) {
        return (a % mod * b % mod) % mod;
    }

    static int maxn = 100005;

    static class sort implements Comparator<String> {
        public int compare(String a, String b) {
            return a.length() - b.length();
        }
    }

    static int func(int a, int b, int x) {
        return ((a * x) / b) - (a * (x / b));
    }

    static void solve() {
        long x = nlo();
        long y = 100;
        long ans = 0;
        for (long i = 1; i < Long.MAX_VALUE; i++) {
            y = (y + (y / 100));
            if (y >= x) {
                ans = i;
                break;
            }
        }
        out.println(ans);
    }
} import java.util.*; util.* java import java.io.*; io.* java public class Main {
    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in), 32768);
    static PrintWriter out = new PrintWriter(System.out);
    static StringTokenizer t;

    static String sn() {
        while (t == null || !t.hasMoreTokens()) {
            try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            }
        }
        return t.nextToken();
    }

    static int ni() {
        return Integer.parseInt(sn());
    }

    static long nlo() {
        return Long.parseLong(sn());
    }

    public static void main(String args[]) {
        int t = 1;//ni();
        while (t-- > 0) {
            solve();
        }
        out.close();
    }

    static long mod = (long) 1e9 + 7;

    static long pro(long a, long b) {
        return (a % mod * b % mod) % mod;
    }

    static int maxn = 100005;

    static class sort implements Comparator<String> {
        public int compare(String a, String b) {
            return a.length() - b.length();
        }
    }

    static int func(int a, int b, int x) {
        return ((a * x) / b) - (a * (x / b));
    }

    static void solve() {
        long x = nlo();
        long y = 100;
        long ans = 0;
        for (long i = 1; i < Long.MAX_VALUE; i++) {
            y = (y + (y / 100));
            if (y >= x) {
                ans = i;
                break;
            }
        }
        out.println(ans);
    }
} Main static BufferedReader br = new BufferedReader(new InputStreamReader(System.in), 32768); br new BufferedReader(new InputStreamReader(System.in), 32768) static PrintWriter out = new PrintWriter(System.out); out new PrintWriter(System.out) static StringTokenizer t; t static long mod = (long) 1e9 + 7; mod (long) 1e9 + 7 (long) 1e9 7 static int maxn = 100005; maxn 100005 static String sn() {
        while (t == null || !t.hasMoreTokens()) {
            try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            }
        }
        return t.nextToken();
    } sn {
        while (t == null || !t.hasMoreTokens()) {
            try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            }
        }
        return t.nextToken();
    } while (t == null || !t.hasMoreTokens()) {
            try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            }
        } t == null || !t.hasMoreTokens() t == null t null !t.hasMoreTokens() t.hasMoreTokens() t.hasMoreTokens t {
            try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            }
        } try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            } catch (IOException e) {
                throw new RuntimeException();
            } IOException e {
                throw new RuntimeException();
            } throw new RuntimeException(); new RuntimeException() {
                t = new StringTokenizer(br.readLine());
            } t = new StringTokenizer(br.readLine()) t new StringTokenizer(br.readLine()) return t.nextToken(); t.nextToken() t.nextToken t static int ni() {
        return Integer.parseInt(sn());
    } ni {
        return Integer.parseInt(sn());
    } return Integer.parseInt(sn()); Integer.parseInt(sn()) Integer.parseInt Integer sn() sn static long nlo() {
        return Long.parseLong(sn());
    } nlo {
        return Long.parseLong(sn());
    } return Long.parseLong(sn()); Long.parseLong(sn()) Long.parseLong Long sn() sn public static void main(String args[]) {
        int t = 1;//ni();
        while (t-- > 0) {
            solve();
        }
        out.close();
    } main {
        int t = 1;//ni();
        while (t-- > 0) {
            solve();
        }
        out.close();
    } int t = 1; t 1 while (t-- > 0) {
            solve();
        } t-- > 0 t-- t 0 {
            solve();
        } solve() solve out.close() out.close out String args[] args static long pro(long a, long b) {
        return (a % mod * b % mod) % mod;
    } pro {
        return (a % mod * b % mod) % mod;
    } return (a % mod * b % mod) % mod; (a % mod * b % mod) % mod (a % mod * b % mod) a % mod * b a % mod a mod b mod mod long a a long b b static int func(int a, int b, int x) {
        return ((a * x) / b) - (a * (x / b));
    } func {
        return ((a * x) / b) - (a * (x / b));
    } return ((a * x) / b) - (a * (x / b)); ((a * x) / b) - (a * (x / b)) ((a * x) / b) (a * x) a x b (a * (x / b)) a (x / b) x b int a a int b b int x x static void solve() {
        long x = nlo();
        long y = 100;
        long ans = 0;
        for (long i = 1; i < Long.MAX_VALUE; i++) {
            y = (y + (y / 100));
            if (y >= x) {
                ans = i;
                break;
            }
        }
        out.println(ans);
    } solve {
        long x = nlo();
        long y = 100;
        long ans = 0;
        for (long i = 1; i < Long.MAX_VALUE; i++) {
            y = (y + (y / 100));
            if (y >= x) {
                ans = i;
                break;
            }
        }
        out.println(ans);
    } long x = nlo(); x nlo() nlo long y = 100; y 100 long ans = 0; ans 0 for (long i = 1; i < Long.MAX_VALUE; i++) {
            y = (y + (y / 100));
            if (y >= 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 {
            y = (y + (y / 100));
            if (y >= x) {
                ans = i;
                break;
            }
        } {
            y = (y + (y / 100));
            if (y >= x) {
                ans = i;
                break;
            }
        } y = (y + (y / 100)) y (y + (y / 100)) y (y / 100) y 100 if (y >= x) {
                ans = i;
                break;
            } y >= x y x {
                ans = i;
                break;
            } ans = i ans i break; out.println(ans) out.println out ans static class sort implements Comparator<String> {
        public int compare(String a, String b) {
            return a.length() - b.length();
        }
    } sort public int compare(String a, String b) {
            return a.length() - b.length();
        } compare {
            return a.length() - b.length();
        } return a.length() - b.length(); a.length() - b.length() a.length() a.length a b.length() b.length b String a a String b b Comparator public class Main {
    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in), 32768);
    static PrintWriter out = new PrintWriter(System.out);
    static StringTokenizer t;

    static String sn() {
        while (t == null || !t.hasMoreTokens()) {
            try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            }
        }
        return t.nextToken();
    }

    static int ni() {
        return Integer.parseInt(sn());
    }

    static long nlo() {
        return Long.parseLong(sn());
    }

    public static void main(String args[]) {
        int t = 1;//ni();
        while (t-- > 0) {
            solve();
        }
        out.close();
    }

    static long mod = (long) 1e9 + 7;

    static long pro(long a, long b) {
        return (a % mod * b % mod) % mod;
    }

    static int maxn = 100005;

    static class sort implements Comparator<String> {
        public int compare(String a, String b) {
            return a.length() - b.length();
        }
    }

    static int func(int a, int b, int x) {
        return ((a * x) / b) - (a * (x / b));
    }

    static void solve() {
        long x = nlo();
        long y = 100;
        long ans = 0;
        for (long i = 1; i < Long.MAX_VALUE; i++) {
            y = (y + (y / 100));
            if (y >= x) {
                ans = i;
                break;
            }
        }
        out.println(ans);
    }
} public class Main {
    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in), 32768);
    static PrintWriter out = new PrintWriter(System.out);
    static StringTokenizer t;

    static String sn() {
        while (t == null || !t.hasMoreTokens()) {
            try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            }
        }
        return t.nextToken();
    }

    static int ni() {
        return Integer.parseInt(sn());
    }

    static long nlo() {
        return Long.parseLong(sn());
    }

    public static void main(String args[]) {
        int t = 1;//ni();
        while (t-- > 0) {
            solve();
        }
        out.close();
    }

    static long mod = (long) 1e9 + 7;

    static long pro(long a, long b) {
        return (a % mod * b % mod) % mod;
    }

    static int maxn = 100005;

    static class sort implements Comparator<String> {
        public int compare(String a, String b) {
            return a.length() - b.length();
        }
    }

    static int func(int a, int b, int x) {
        return ((a * x) / b) - (a * (x / b));
    }

    static void solve() {
        long x = nlo();
        long y = 100;
        long ans = 0;
        for (long i = 1; i < Long.MAX_VALUE; i++) {
            y = (y + (y / 100));
            if (y >= x) {
                ans = i;
                break;
            }
        }
        out.println(ans);
    }
} Main
import java.util.*;
import java.io.*;

public class Main {
    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in), 32768);
    static PrintWriter out = new PrintWriter(System.out);
    static StringTokenizer t;

    static String sn() {
        while (t == null || !t.hasMoreTokens()) {
            try {
                t = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException();
            }
        }
        return t.nextToken();
    }

    static int ni() {
        return Integer.parseInt(sn());
    }

    static long nlo() {
        return Long.parseLong(sn());
    }

    public static void main(String args[]) {
        int t = 1;//ni();
        while (t-- > 0) {
            solve();
        }
        out.close();
    }

    static long mod = (long) 1e9 + 7;

    static long pro(long a, long b) {
        return (a % mod * b % mod) % mod;
    }

    static int maxn = 100005;

    static class sort implements Comparator<String> {
        public int compare(String a, String b) {
            return a.length() - b.length();
        }
    }

    static int func(int a, int b, int x) {
        return ((a * x) / b) - (a * (x / b));
    }

    static void solve() {
        long x = nlo();
        long y = 100;
        long ans = 0;
        for (long i = 1; i < Long.MAX_VALUE; i++) {
            y = (y + (y / 100));
            if (y >= x) {
                ans = i;
                break;
            }
        }
        out.println(ans);
    }
}