Triangle Counting UVA11401

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <queue>
#include <algorithm>
#include <vector>
#include <cstring>
#include <stack>
#include <cctype>
#include <utility>   
#include <map>
#include <string>  
#include <climits> 
#include <set>
#include <string> 
#include <sstream>
#include <utility>   
#include <ctime>
 
using std::priority_queue;
using std::vector;
using std::swap;
using std::stack;
using std::sort;
using std::max;
using std::min;
using std::pair;
using std::map;
using std::string;
using std::cin;
using std::cout;
using std::set;
using std::queue;
using std::string;
using std::istringstream;
using std::make_pair;
using std::greater;
using std::endl;

const int MAXN(1000010);

long long table[MAXN];

int main()
{
	for(long long i = 3; i <= 1000000LL; ++i)
		table[i] = table[i-1]+((i-1)*(i-2)/2-(i-i/2-1))/2;
	int n; 
	while(scanf("%d", &n), n >= 3)
	{
		cout << table[n] << "\n";
	}
	return 0;
}