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#include <bits/stdc++.h>
using namespace std;

const long long SUM = 20'000 * 500 * 3 + 999;

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

    vector<long long> t(n);
    vector<long long> p(n + 1, 0);
    vector<long long> sums(2 * SUM, 0);

    for (int i = 0; i < n; i++) {
        cin >> t[i];
        p[i + 1] = t[i] + p[i];
    }

    // unordered_map<long long, long long> m;
    long long ans = 0;

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) { 
            for (int k = j + 1; k < n + 1; k++) {
                // m[-((p[k] - p[j]) - p[i])]++;
                sums[-((p[k] - p[j]) - p[i]) + SUM]++;
            }
        }
        for (int j = 0; j < n; j++) { 
            for (int k = j + 1; k < n + 1; k++) {
                // ans += m[(p[i + 1] + (p[k] - p[j]))];
                ans += sums[(p[i + 1] + (p[k] - p[j])) + SUM];
            }
        }
    }

    std::fill(sums.begin(), sums.end(), 0);

    for (int i = 0; i < n; i++) {
        for (int j = i + 1; j < n + 1; j++) {
            sums[p[j] - p[i] + SUM]++;
        }
    }

    for (int i = 0; i < n; i++) {
        for (int j = i + 1; j < n + 1; j++) {
            if (abs(p[j] - p[i]) > SUM - 99)
                continue;
            if ((p[j] - p[i]) != 0 && sums[-2 * (p[j] - p[i]) + SUM]){
                ans -= sums[-2 * (p[j] - p[i]) + SUM] * 3 ;
            } else if (p[j] - p[i] == 0) {
                ans -= (sums[-2 * (p[j] - p[i]) + SUM] - 1) * 3;
                ans--;
            }
        }
    }

    cout << ans / 6 << "\n";
}