import java.util.Scanner;

public class test { public static void main(String[] args) {

Scanner reader=new Scanner(System.in);		System.out.print("请输入n:");		int n=reader.nextInt();		double sum=0.0;		double x;		for(int i=1;i<=n;i++){		   		   x=(double)(1.0/i);//保证得到是小数		   System.out.print("x="+x);		   sum=sum+x;		}         String result=String.format("%.2f",sum);//保存两位小数		System.out.print("1+1/2=1/n=sum="+result);	}

}