import java.util.*;

public class Main {
	Scanner sc = new Scanner(System.in);
	final int MOD = 998244353;
	final int MAX = Integer.MAX_VALUE;
	final long LMAX = Long.MAX_VALUE;
	int len = (int)1e6 + 1;
	
	
	void doIt() {
		long X = sc.nextLong();
		long num = 100;
		int cur = 0;
		
		while(X > num) {
			num *= 1.01;
			cur++;
		}
		System.out.println(cur);
	}
	
	
	public static void main(String[] args) {
		new Main().doIt();
	}

} import java.util.*; util.* java public class Main {
	Scanner sc = new Scanner(System.in);
	final int MOD = 998244353;
	final int MAX = Integer.MAX_VALUE;
	final long LMAX = Long.MAX_VALUE;
	int len = (int)1e6 + 1;
	
	
	void doIt() {
		long X = sc.nextLong();
		long num = 100;
		int cur = 0;
		
		while(X > num) {
			num *= 1.01;
			cur++;
		}
		System.out.println(cur);
	}
	
	
	public static void main(String[] args) {
		new Main().doIt();
	}

} Main Scanner sc = new Scanner(System.in); sc new Scanner(System.in) final int MOD = 998244353; MOD 998244353 final int MAX = Integer.MAX_VALUE; MAX Integer.MAX_VALUE Integer Integer.MAX_VALUE final long LMAX = Long.MAX_VALUE; LMAX Long.MAX_VALUE Long Long.MAX_VALUE int len = (int)1e6 + 1; len (int)1e6 + 1 (int)1e6 1 void doIt() {
		long X = sc.nextLong();
		long num = 100;
		int cur = 0;
		
		while(X > num) {
			num *= 1.01;
			cur++;
		}
		System.out.println(cur);
	} doIt {
		long X = sc.nextLong();
		long num = 100;
		int cur = 0;
		
		while(X > num) {
			num *= 1.01;
			cur++;
		}
		System.out.println(cur);
	} long X = sc.nextLong(); X sc.nextLong() sc.nextLong sc long num = 100; num 100 int cur = 0; cur 0 while(X > num) {
			num *= 1.01;
			cur++;
		} X > num X num {
			num *= 1.01;
			cur++;
		} num *= 1.01 num 1.01 cur++ cur System.out.println(cur) System.out.println System.out System System.out cur public static void main(String[] args) {
		new Main().doIt();
	} main {
		new Main().doIt();
	} new Main().doIt() new Main().doIt new Main() String[] args args public class Main {
	Scanner sc = new Scanner(System.in);
	final int MOD = 998244353;
	final int MAX = Integer.MAX_VALUE;
	final long LMAX = Long.MAX_VALUE;
	int len = (int)1e6 + 1;
	
	
	void doIt() {
		long X = sc.nextLong();
		long num = 100;
		int cur = 0;
		
		while(X > num) {
			num *= 1.01;
			cur++;
		}
		System.out.println(cur);
	}
	
	
	public static void main(String[] args) {
		new Main().doIt();
	}

} public class Main {
	Scanner sc = new Scanner(System.in);
	final int MOD = 998244353;
	final int MAX = Integer.MAX_VALUE;
	final long LMAX = Long.MAX_VALUE;
	int len = (int)1e6 + 1;
	
	
	void doIt() {
		long X = sc.nextLong();
		long num = 100;
		int cur = 0;
		
		while(X > num) {
			num *= 1.01;
			cur++;
		}
		System.out.println(cur);
	}
	
	
	public static void main(String[] args) {
		new Main().doIt();
	}

} Main
import java.util.*;

public class Main {
	Scanner sc = new Scanner(System.in);
	final int MOD = 998244353;
	final int MAX = Integer.MAX_VALUE;
	final long LMAX = Long.MAX_VALUE;
	int len = (int)1e6 + 1;
	
	
	void doIt() {
		long X = sc.nextLong();
		long num = 100;
		int cur = 0;
		
		while(X > num) {
			num *= 1.01;
			cur++;
		}
		System.out.println(cur);
	}
	
	
	public static void main(String[] args) {
		new Main().doIt();
	}

}
