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#include <iostream>
#include <vector>
#include <unordered_map>
#include <map>

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    std::cin.tie(nullptr);

    short n;
    cin >> n;

    vector<short> numbers;
    short number;
    short maxAbs = 0;
    for (short i = 0; i < n; i++) {
        cin >> number;
        numbers.push_back(number);
        if (abs(number) > maxAbs) {
            maxAbs = abs(number);
        }
    }

    unordered_map<int, int> sums;
    vector<int> prefixes;
    prefixes.push_back(0);
    for (short i = 0; i < n; i++) {
        int sum = 0;
        for (short j = i; j < n; j++) {
            sum += numbers[j];
            sums[sum]++;
            if (i == 0) {
                prefixes.push_back(sum);
            }
        }
    }

    int halfSize = 2 * n * maxAbs + 1;
    vector<vector<pair<short, int>>> beginningsAndSums(2 * halfSize);
    vector<vector<pair<short, int>>> endsAndSums(2 * halfSize);
    for (short i = 0; i < prefixes.size(); i++) {
        for (auto &sum : sums) {
            if (i < prefixes.size() - 1) {
                beginningsAndSums[halfSize - prefixes[i] + sum.first].push_back({i, sum.second});
            }
            if (i > 0) {
                endsAndSums[halfSize + prefixes[i] + sum.first].push_back({i, sum.second});
            }
        }
    }
    prefixes.clear();

    vector<int> endsAndSumsSums(2 * halfSize);
    for (int i = 0; i < endsAndSums.size(); i++) {
        int sum = 0;
        for (int j = 0; j < endsAndSums[i].size(); j++) {
            sum += endsAndSums[i][j].second;
        }
        endsAndSumsSums[i] = sum;
    }

    long long result = 0;
    for (int i = 0; i < beginningsAndSums.size(); i++) {
        if (endsAndSums[2 * halfSize - i].size() > 0) {
            vector<pair<short, int>> &beginAndSum = beginningsAndSums[i];
            vector<pair<short, int>> &endAndSum = endsAndSums[2 * halfSize - i];
            int beginIter = 0;
            int endIter = 0;
            int sum = endsAndSumsSums[2 * halfSize - i];
            while (beginIter < beginAndSum.size() && endIter < endAndSum.size()) {
                if (beginAndSum[beginIter].first < endAndSum[endIter].first) {
                    result += 1LL * sum * beginAndSum[beginIter].second;
                    beginIter++;
                } else {
                    sum -= endAndSum[endIter].second;
                    endIter++;
                }
            }
        }
    }
    beginningsAndSums.clear();
    endsAndSums.clear();
    endsAndSumsSums.clear();

    for (auto &sum : sums) {
        if (sums.contains(-2 * sum.first)) {
            int doubleSum = sums[-2 * sum.first];
            if (sum.first == 0) {
                result -= 3LL * doubleSum * (doubleSum - 1) + doubleSum;
            } else {
                result -= 3LL * sum.second * doubleSum;
            }
        }
    }

    cout << (result / 6);
}