zoj 2773

Triangular Sums
Time Limit: 1 Second     
Memory Limit: 32768 KB
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..n; k*T(k+1)]
Input
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.
Output
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.
Sample Input
434510
Sample Output
1 3 452 4 1053 5 2104 10 2145
 
//2773 #include using namespace std; intmain () {intn;cin>>n;inti=0;while (n--) {intnum;cin>num;i++;long r=0;//여기서 int/long/long long을 사용하면 for(intk=1;k<=num;k+) {r+=(k*(k+1)*(k+2)/2);}cout<

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