NYOJ122Triangular Sums

Triangular Sums

时间限制：3000 ms  |  内存限制：65535 KB

难度：2

 

描述

The n^th 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…n; k * 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

 
#include<stdio.h>
#include<string.h>
int shu[310];
int main()
{
    int n,i,j,k,x;
    long long t;
    for(i=0;i<310;i++)
    shu[i]=i*(i+1)/2;
    scanf("%d",&n);
   for(k=1;k<=n;k++)
   {
      scanf("%d",&x);
      t=0;
      for(i=1;i<=x;i++)
      t+=shu[i+1]*i;
      printf("%d %d %lld\n",k,x,t);
   }
   return 0;
}