import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sca = new Scanner(System.in);
		long x = sca.nextLong();
		long money = 100;
		int year = 1;
		boolean flag = false;

		do {
			money = money + (money/100);
			if(money >= x) {
				System.out.println(year);
				flag = true;
			}
			year++;
		} while(!flag);

		// 後始末
		sca.close();
	}
} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner sca = new Scanner(System.in);
		long x = sca.nextLong();
		long money = 100;
		int year = 1;
		boolean flag = false;

		do {
			money = money + (money/100);
			if(money >= x) {
				System.out.println(year);
				flag = true;
			}
			year++;
		} while(!flag);

		// 後始末
		sca.close();
	}
} Main public static void main(String[] args) {
		Scanner sca = new Scanner(System.in);
		long x = sca.nextLong();
		long money = 100;
		int year = 1;
		boolean flag = false;

		do {
			money = money + (money/100);
			if(money >= x) {
				System.out.println(year);
				flag = true;
			}
			year++;
		} while(!flag);

		// 後始末
		sca.close();
	} main {
		Scanner sca = new Scanner(System.in);
		long x = sca.nextLong();
		long money = 100;
		int year = 1;
		boolean flag = false;

		do {
			money = money + (money/100);
			if(money >= x) {
				System.out.println(year);
				flag = true;
			}
			year++;
		} while(!flag);

		// 後始末
		sca.close();
	} Scanner sca = new Scanner(System.in); sca new Scanner(System.in) long x = sca.nextLong(); x sca.nextLong() sca.nextLong sca long money = 100; money 100 int year = 1; year 1 boolean flag = false; flag false do {
			money = money + (money/100);
			if(money >= x) {
				System.out.println(year);
				flag = true;
			}
			year++;
		} while(!flag); !flag flag {
			money = money + (money/100);
			if(money >= x) {
				System.out.println(year);
				flag = true;
			}
			year++;
		} money = money + (money/100) money money + (money/100) money (money/100) money 100 if(money >= x) {
				System.out.println(year);
				flag = true;
			} money >= x money x {
				System.out.println(year);
				flag = true;
			} System.out.println(year) System.out.println System.out System System.out year flag = true flag true year++ year sca.close() sca.close sca String[] args args public class Main {

	public static void main(String[] args) {
		Scanner sca = new Scanner(System.in);
		long x = sca.nextLong();
		long money = 100;
		int year = 1;
		boolean flag = false;

		do {
			money = money + (money/100);
			if(money >= x) {
				System.out.println(year);
				flag = true;
			}
			year++;
		} while(!flag);

		// 後始末
		sca.close();
	}
} public class Main {

	public static void main(String[] args) {
		Scanner sca = new Scanner(System.in);
		long x = sca.nextLong();
		long money = 100;
		int year = 1;
		boolean flag = false;

		do {
			money = money + (money/100);
			if(money >= x) {
				System.out.println(year);
				flag = true;
			}
			year++;
		} while(!flag);

		// 後始末
		sca.close();
	}
} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sca = new Scanner(System.in);
		long x = sca.nextLong();
		long money = 100;
		int year = 1;
		boolean flag = false;

		do {
			money = money + (money/100);
			if(money >= x) {
				System.out.println(year);
				flag = true;
			}
			year++;
		} while(!flag);

		// 後始末
		sca.close();
	}
}