Triangular Sums

描述

The nth Triangular number, T(n) = 1 + … + n, is the sum of the first n integers. It is the number of points in a triangular array with n points on side. For example T(4):

X
X X
X X X
X X X X

Write a program to compute the weighted sum of triangular numbers:

W(n) = SUM[k = 1…nk * T(k + 1)]

 
输入
The first line of input contains a single integer N, (1 ≤ N ≤ 1000) which is the number of datasets that follow.

Each dataset consists of a single line of input containing a single integer n, (1 ≤ n ≤300), which is the number of points on a side of the triangle.
输出
For each dataset, output on a single line the dataset number (1 through N), a blank, the value of n for the dataset, a blank, and the weighted sum ,W(n), of triangular numbers for n.
样例输入
4
3
4
5
10
样例输出
1 3 45
2 4 105
3 5 210
4 10 2145

 1 import java.text.NumberFormat;
 2 import java.util.Arrays;
 3 import java.util.Scanner;
 4 
 5 public class Main {
 6     public static void main(String[] args) {
 7         Scanner scanner=new Scanner(System.in);
 8         int T;
 9         int n;
10         int k;
11         int i;
12         int temp;
13         int sum;
14         int time=1;
15         
16         T=scanner.nextInt();
17         while(true){
18             if(T==0)
19                 break;
20             T--;
21             
22             n=scanner.nextInt();
23             
24             sum=0;
25             for(k=1;k<=n;k++){
26                 temp=0;
27                 for(i=1;i<=k+1;i++)
28                     temp+=i;
29                 
30                 sum+=k*temp;
31             }
32             System.out.println(time+" "+n+" "+sum);
33             time++;
34         }
35     } 
36 }

 

 
posted @ 2014-11-29 21:46  zqxLonely  阅读(257)  评论(0编辑  收藏  举报