計算1+1/2+....1/n

import java.text.DecimalFormat;
import java.util.Scanner;

public class b {
	public static void main(String[] args) {
		
		Scanner sc=new Scanner(System.in);
		int n =sc.nextInt();
		DecimalFormat df=new DecimalFormat("0.000000");
		double sum=0;
		for(int i=1;i<=n;i++)
			sum+=1.0/i;//1.0記住
		System.out.println(df.format(sum));
	}
}