import java.util.Scanner;
public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		long x = sc.nextLong();
		long  dep = 100;
		double rate = 1.01;

		for(int i = 1; i <= 4000; i++) {
			dep *= 1.01;
			if(dep >= x) {
				System.out.println(i);
				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