import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
double k = in.nextDouble();
double i = 1;
double sn = 0;
while(! (sn > k) ){
sn = sn + 1/i;
i++;
}
System.out.println( (int)(i-1) );
}
}