import java.util.Scanner;

public class P1035_1029 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scanner=new Scanner(System.in);
		int i，k=scanner.nextInt();
		double S=0;
		for (i = 1;; i++) {
			S+=1.0/i;
			if(S>k){ 
				System.out.println(i);
				break;
				}
		}
		
	}

}