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#include <bits/stdc++.h>

using namespace std;
using LL = long long;
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
#define ssize(x) int(x.size())

template<class A, class B> auto &operator<<(ostream &o, pair<A, B> p) {
    return o << '(' << p.first << ", " << p.second << ')';
}

template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) {
    o << '{'; int i = 0; for (auto e : x) o << (", ")+2*!i++ << e;
    return o << '}';
}

#ifdef DEBUG
#define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n';
#else
#define debug(...) {}
#endif


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

    int n;
    int mx = 0;
    cin >> n;
    vector<int> a(n + 1), pref(n + 1);
    FOR(i, 1, n) {
        cin >> a[i];
        pref[i] = a[i] + pref[i - 1];
        mx = max(mx, abs(pref[i]));
    }

    int mx_sum = 3 * mx;
    vector<int> sums(2 * mx_sum + 1);

    LL ans = 0;
    FOR(i1, 0, n) {
        FOR(k1, 0, n) {
            FOR(k2, k1 + 1, n)
                ans += sums[mx_sum + pref[i1] + pref[k2] - pref[k1]];
        }

        FOR(j1, 0, n) {
            FOR(j2, j1 + 1, n)
                sums[mx_sum + pref[i1] + pref[j1] - pref[j2]]++;
        }
    }

    map<int, int> segs;
    FOR(i, 0, n) {
        FOR(j, i + 1, n) {
            segs[2 * (pref[i] - pref[j])]++;
            if (pref[i] == pref[j])
                ans += 2;
        }
    }

    FOR(i, 0, n) {
        FOR(j, i + 1, n)
            ans -= 3 * segs[pref[j] - pref[i]];
    }

    cout << ans / 6 << '\n';

    return 0;
}