import java.util.Scanner;

public class Main {

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

		long yokin = 100;
		// 目標金額
		long purpose = sc.nextLong();
		// 経過年度
		int year = 0;

		while(true) {
			if(yokin >= purpose) {
				System.out.println(year);
				break;
			}

			yokin = (long) (yokin * 1.01);
			year++;
		}

		sc.close();
	}


}

/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