import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        //コード
    	Scanner sc = new Scanner(System.in);
//    	File file = new File("src/in.txt");
//    	Scanner sc = new Scanner(file);
    	long X = sc.nextLong();
    	int year = 0;
    	long sum = 100;

    	while(sum < X) {
    		year = year + 1;
    		sum = (long) (sum + Math.floor(sum * 0.01));
    	}
    	System.out.println(year);
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        //コード
    	Scanner sc = new Scanner(System.in);
//    	File file = new File("src/in.txt");
//    	Scanner sc = new Scanner(file);
    	long X = sc.nextLong();
    	int year = 0;
    	long sum = 100;

    	while(sum < X) {
    		year = year + 1;
    		sum = (long) (sum + Math.floor(sum * 0.01));
    	}
    	System.out.println(year);
    }
} Main public static void main(String[] args) {
        //コード
    	Scanner sc = new Scanner(System.in);
//    	File file = new File("src/in.txt");
//    	Scanner sc = new Scanner(file);
    	long X = sc.nextLong();
    	int year = 0;
    	long sum = 100;

    	while(sum < X) {
    		year = year + 1;
    		sum = (long) (sum + Math.floor(sum * 0.01));
    	}
    	System.out.println(year);
    } main {
        //コード
    	Scanner sc = new Scanner(System.in);
//    	File file = new File("src/in.txt");
//    	Scanner sc = new Scanner(file);
    	long X = sc.nextLong();
    	int year = 0;
    	long sum = 100;

    	while(sum < X) {
    		year = year + 1;
    		sum = (long) (sum + Math.floor(sum * 0.01));
    	}
    	System.out.println(year);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) long X = sc.nextLong(); X sc.nextLong() sc.nextLong sc int year = 0; year 0 long sum = 100; sum 100 while(sum < X) {
    		year = year + 1;
    		sum = (long) (sum + Math.floor(sum * 0.01));
    	} sum < X sum X {
    		year = year + 1;
    		sum = (long) (sum + Math.floor(sum * 0.01));
    	} year = year + 1 year year + 1 year 1 sum = (long) (sum + Math.floor(sum * 0.01)) sum (long) (sum + Math.floor(sum * 0.01)) sum Math.floor(sum * 0.01) Math.floor Math sum * 0.01 sum 0.01 System.out.println(year) System.out.println System.out System System.out year String[] args args public class Main {
    public static void main(String[] args) {
        //コード
    	Scanner sc = new Scanner(System.in);
//    	File file = new File("src/in.txt");
//    	Scanner sc = new Scanner(file);
    	long X = sc.nextLong();
    	int year = 0;
    	long sum = 100;

    	while(sum < X) {
    		year = year + 1;
    		sum = (long) (sum + Math.floor(sum * 0.01));
    	}
    	System.out.println(year);
    }
} public class Main {
    public static void main(String[] args) {
        //コード
    	Scanner sc = new Scanner(System.in);
//    	File file = new File("src/in.txt");
//    	Scanner sc = new Scanner(file);
    	long X = sc.nextLong();
    	int year = 0;
    	long sum = 100;

    	while(sum < X) {
    		year = year + 1;
    		sum = (long) (sum + Math.floor(sum * 0.01));
    	}
    	System.out.println(year);
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        //コード
    	Scanner sc = new Scanner(System.in);
//    	File file = new File("src/in.txt");
//    	Scanner sc = new Scanner(file);
    	long X = sc.nextLong();
    	int year = 0;
    	long sum = 100;

    	while(sum < X) {
    		year = year + 1;
    		sum = (long) (sum + Math.floor(sum * 0.01));
    	}
    	System.out.println(year);
    }
}