SPOJ 1167(Move To Invert-三角形硬币阵颠倒)

For h=4 at least 3 coins must be moved to invert it.

Input

In the first line N will be given and then N lines follow with each line having a integer which is the height of triangle in that test case.00≤h<10¹⁰;

Output

For each test case output in a seperate line the minimum number of moves required to invert the triangle. Output fits in long long data type

Example

Inputt: 1 3 Output: 2

答案是n(n+1) div 6

这是纯粹的打表找规律题……

注意Comments中对%lli的注解（等待C++有识之士解释……）

#include<cstdio>
#include<cstring>
using namespace std;
unsigned long long n;
int main()
{
  scanf("%lli",&n);
  while (scanf("%lli",&n)!=EOF) printf("%lli\n",n*(n+1)/6);
  return 0;
}