import java.util.*;

class Main {
    public static void main(String args[]) {
        Scanner inp = new Scanner(System.in);
        long k = inp.nextLong();
        long s = 100;
        long c = 0;
        while (true) {
            c++;
            s = ( long ) ( ( ( double )s ) * 1.01);
            if (s >= k) {
                System.out.println(c);
                break;
            }
        }
    }
} import java.util.*; util.* java class Main {
    public static void main(String args[]) {
        Scanner inp = new Scanner(System.in);
        long k = inp.nextLong();
        long s = 100;
        long c = 0;
        while (true) {
            c++;
            s = ( long ) ( ( ( double )s ) * 1.01);
            if (s >= k) {
                System.out.println(c);
                break;
            }
        }
    }
} Main public static void main(String args[]) {
        Scanner inp = new Scanner(System.in);
        long k = inp.nextLong();
        long s = 100;
        long c = 0;
        while (true) {
            c++;
            s = ( long ) ( ( ( double )s ) * 1.01);
            if (s >= k) {
                System.out.println(c);
                break;
            }
        }
    } main {
        Scanner inp = new Scanner(System.in);
        long k = inp.nextLong();
        long s = 100;
        long c = 0;
        while (true) {
            c++;
            s = ( long ) ( ( ( double )s ) * 1.01);
            if (s >= k) {
                System.out.println(c);
                break;
            }
        }
    } Scanner inp = new Scanner(System.in); inp new Scanner(System.in) long k = inp.nextLong(); k inp.nextLong() inp.nextLong inp long s = 100; s 100 long c = 0; c 0 while (true) {
            c++;
            s = ( long ) ( ( ( double )s ) * 1.01);
            if (s >= k) {
                System.out.println(c);
                break;
            }
        } true {
            c++;
            s = ( long ) ( ( ( double )s ) * 1.01);
            if (s >= k) {
                System.out.println(c);
                break;
            }
        } c++ c s = ( long ) ( ( ( double )s ) * 1.01) s ( long ) ( ( ( double )s ) * 1.01) ( ( double )s ) 1.01 if (s >= k) {
                System.out.println(c);
                break;
            } s >= k s k {
                System.out.println(c);
                break;
            } System.out.println(c) System.out.println System.out System System.out c break; String args[] args
import java.util.*;

class Main {
    public static void main(String args[]) {
        Scanner inp = new Scanner(System.in);
        long k = inp.nextLong();
        long s = 100;
        long c = 0;
        while (true) {
            c++;
            s = ( long ) ( ( ( double )s ) * 1.01);
            if (s >= k) {
                System.out.println(c);
                break;
            }
        }
    }
}