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#include <bits/stdc++.h>
using namespace std;
int main() {
    cin.tie(0)->sync_with_stdio(false);
    int n;
    cin >> n;
    vector<int> uc(n);
    for (int &x : uc) cin >> x;
    vector<int> buc;
    buc.reserve(n * (n + 1) / 2);
    for (int i = 0; i < n; i++) {
        for (int ts = 0, j = i; j < n; j++) buc.push_back(ts += uc[j]);
    }
    sort(buc.begin(), buc.end());
    // copy(buc.begin(), buc.end(), ostream_iterator<int>(cout, " ")); cout << endl;
    int m = buc.size();
    long long cnt = 0;
    vector<long long> ubuc, ubcnt;
    unordered_map<int, long long> ucm;
    ubuc.reserve(m);
    long long p = buc[0] - 1;
    // compress
    for (int i = 0; i < m; i++) {
        if (buc[i] != p) ubuc.push_back(p = buc[i]);
        ucm[p] += 1;
    }
    int k = ubuc.size();
    ubcnt.resize(k);
    for (int i = 0; i < k; i++) ubcnt[i] = ucm[ubuc[i]];
    // 1sum = many zeroes?
    if (ucm[0] >= 3) {
        cnt = ucm[0] * (ucm[0] - 1) * (ucm[0] - 2) / 6;
    }
    // 2sum
    for (int i = 0; i < k; i++) {
        if (ubuc[i] == 0) continue;
        long long cl = ubcnt[i];
        if (cl < 2) continue;
        long long sv = -2 * ubuc[i];
        long long cr = ucm[sv];
        cnt += cl * (cl - 1) * cr / 2;
    }
    // 3sum
    for (int i = 0; i < k - 2; i++) {
        int l = i + 1, r = k - 1;
        if (ubuc[i] + ubuc[l] > 0) continue;
        while (l < r) {
            long long cm = ubcnt[i];
            long long sum3 = ubuc[i] + ubuc[l] + ubuc[r];
            if (sum3 == 0) {
                long long cl = ubcnt[l];
                long long cr = ubcnt[r];
                // cout << ubuc[i] << "*" << cm << "," << ubuc[l] << "*" << cl << "," << ubuc[r] << "*" << cr << endl;
                cnt += cl * cr * cm;
                l += 1;
                r -= 1;
            } else if (sum3 < 0) {
                l += 1;
            } else {
                r -= 1;
            }
        }
    }
    cout << cnt << endl;
    return 0;
}