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

int main() {
    int n;
    std::cin >> n;

    std::vector<int> uc;
    std::unordered_map<int, int64_t> subsums;
    for (int i = 0; i < n; ++i) {
        int in;
        std::cin >> in;
        uc.emplace_back(in);

        int subsum = 0;
        for (auto it = uc.rbegin(); it != uc.rend(); ++it) {
            subsum += *it;
            subsums[subsum] += 1;
        }
    }

    int64_t ret = 0;

    for (auto [s1, c1]: subsums) {
        for (auto [s2, c2]: subsums) {
            if (s1 >= s2) {
                continue;
            }

            int s12 = s1 + s2;
            int64_t c12 = c1 * c2;

            if (s2 >= -s12) {
                continue;
            }

            if (subsums.count(-s12)) {
                int64_t c3 = subsums[-s12];
                int c123 = c12 * c3;
                ret += c123;
            }
        }
    }

    for (auto [s, c]: subsums) {
        int s12 = s * 2;
        int64_t c12 = c * (c - 1) / 2;

        if (s == 0) {
            continue;
        }

        if (subsums.count(-s12)) {
            int64_t c3 = subsums[-s12];
            int c123 = c12 * c3;
            ret += c123;
        }
    }

    if (subsums.count(0)) {
        int64_t c123 = subsums[0] * (subsums[0] - 1) * (subsums[0] - 2) / 6;
        ret += c123;
    }

    std::cout << ret << "\n";
}