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#include <cassert>
#include <iostream>
#include <istream>
#include <fstream>
#include <algorithm>
#include <cstdio>
#include <complex>
#include <vector>
#include <set>
#include <map>
#include <cmath>
#include <queue>
#include <string>
#include <cstdlib>
#include <memory>
#include <ctime>
#include <bitset>
#include <queue>
#include <stack>
#include <unordered_map>
#include <unordered_set>
#include <bitset>
#include <ranges>

using namespace std;

class Buc2024
{
	int n;
	vector<long> input;
	vector<long> left;
	vector<long> right;
	long sum = 0;
	int res = 0;

public:

	void Prep() {
		for (int i = 0; i < n; i++) {
			if (i == 0) {
				left[i] = 0;
			} else {
				left[i] = left[i - 1] + input[i - 1];
			}
		}

		for (int i = n - 1; i >= 0; i--) {
			if (i == (n - 1)) {
				right[i] = 0;
			} else {
				right[i] = right[i + 1] + input[i + 1];
			}
		}
	}

	long threeSum(vector<long>& nums) {
		int n = nums.size();
		bool found = false;
		long count = 0;

		for (int i = 0; i < n - 2; ++i) {
			for (int j = i + 1; j < n - 1; ++j) {
				for (int k = j + 1; k < n; ++k) {
					if (nums[i] + nums[j] + nums[k] == 0) {
						found = true;
						count++;
						//cout << "[" << nums[i] << ", " << nums[j] << ", " << nums[k] << "]" << endl;
					}
				}
			}
		}
		return count;
	}


	long threeSumCount(vector<long>& nums) {
		long count = 0;
		int n = nums.size();

		// Sort the input array
		sort(nums.begin(), nums.end());

		for (int i = 0; i < n - 2; ++i) {
			int left = i + 1;
			int right = n - 1;

			while (left < right) {
				long sum = nums[i] + nums[left] + nums[right];

				if (sum == 0) {
					count++;

					// Move the pointers to find more triplets
					left++;
					right--;
				}
				else if (sum < 0) {
					left++;
				}
				else {
					right--;
				}
			}
		}

		return count;
	}

	void virtual Solve()
	{
		cin >> n;

		input = vector<long>(n, 0);
		left = vector<long>(n, 0);
		right = vector<long>(n, 0);

		//READ:
		for (int i = 0; i < n; i++) {
			cin >> input[i];
			sum += input[i];
		}

		this->Prep();

		vector<long> sol;
		for (int i = 0; i < n; i++) {
			for (int j = i; j < n; j++) {
				long elem = sum - (left[i] + right[j]);
				sol.push_back(elem);
			}
		}

		int result = threeSum(sol);

		cout << result;
		

	}


};

int main()
{
	Buc2024* p = new Buc2024();
	p->Solve();
	delete p;
	return 0;
}