E0065.cpp

// Problem Code: NOTATRI

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int numberOfTriples(vector<int> L) {
	int bound, triples = 0;
	sort(L.begin(), L.end());
	for (int i = 0 ; i < L.size() - 2; i++)
		for (int k, j = i + 1 ; j < L.size() - 1 ; j++) {
			bound = L[i] + L[j];
			k = j + 1;
			triples += L.size() - distance(L.begin(), upper_bound(L.begin() + k, L.end(), bound));
		}
	return triples;
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	int n;
	while (cin >> n, n > 0) {
		vector<int> L(n);
		for (int i = 0 ; i < n ; i++)
			cin >> L[i];
		cout << numberOfTriples(L) << endl;
	}
	return 0;
}