计算一加二分之一加三分之一··前N项和

import java.util.Scanner;

public class Test {
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        double sum = 0;
        for(int i=1;i<=n;i++){
            sum += 1.0/i;
        }
        System.out.printf("sum = %.6f", sum);
    }
}