import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.math.BigDecimal;
import java.util.StringTokenizer;

public class Main {

	public static void main(String[] args) {
		FastScanner sc = new FastScanner(System.in);
		BigDecimal n = BigDecimal.valueOf(100);
		BigDecimal a = BigDecimal.valueOf(Long.parseLong(sc.next()));
		BigDecimal b = BigDecimal.valueOf(1.01);
		int count = 0;
		while (n.compareTo(a) < 0) {
			n = n.multiply(b);
			n = n.setScale(0, BigDecimal.ROUND_FLOOR);
			count++;
		}
		System.out.println(count);

	}

	static class FastScanner {
		private BufferedReader reader;
		private StringTokenizer tokenizer;

		public FastScanner(InputStream in) {
			reader = new BufferedReader(new InputStreamReader(in));
			tokenizer = null;
		}

		public String next() {
			if (tokenizer == null || !tokenizer.hasMoreTokens()) {
				try {
					tokenizer = new StringTokenizer(reader.readLine());
				} catch (IOException e) {
					throw new RuntimeException(e);
				}
			}
			return tokenizer.nextToken();
		}

		public String nextLine() {
			if (tokenizer == null || !tokenizer.hasMoreTokens()) {
				try {
					return reader.readLine();
				} catch (IOException e) {
					throw new RuntimeException(e);
				}
			}

			return tokenizer.nextToken("\n");
		}

		public long nextLong() {
			return Long.parseLong(next());
		}

		public int nextInt() {
			return Integer.parseInt(next());
		}

		public double nextDouble() {
			return Double.parseDouble(next());
		}

		public long[] nextLongArray(int n) {
			long[] a = new long[n];
			for (int i = 0; i < n; i++)
				a[i] = nextLong();
			return a;
		}
	}
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz