1049（15）

两个超时

package com.company;

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

public class Main {

    public static void main(String[] args) {
	// write your code here
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        double[] arr=new double[n];
        DecimalFormat df=new DecimalFormat("0.00");
        for (int i=0;i<arr.length;i++){
            arr[i]=sc.nextDouble();
        }
        double sum=0;
        for (int i=0;i<arr.length;i++){
            double s=0;
            for (int j=i;j<arr.length;j++){
                s=s+arr[j];
                sum=sum+s;
            }
        }
        System.out.println(df.format(sum));
    }
}