//B
import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String xs = sc.next();
      	long x = Long.parseLong(xs);
		long count = 100;
		int max = 10000000;
		
		for (int i = 0; i < max; i++) {
			count = (long)((double)count * 1.01);
			if (count >= x) {
				System.out.println(i + 1);
				break;
			}
		}
	}
}
/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