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#include <bits/stdc++.h>
#define dbg(x) " [" << #x << ": " << (x) << "] "
using namespace std;
using ll = long long;
template<typename A, typename B>
ostream& operator<<(ostream& out, const pair<A,B>& p) {
    return out << "(" << p.first << ", " << p.second << ")";
}
template<typename T>
ostream& operator<<(ostream& out, const vector<T>& c) {
    out << "{";
    for(auto it = c.begin(); it != c.end(); it++) {
        if(it != c.begin()) out << ", ";
        out << *it;
    }
    return out << "}";
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin >> n;
    vector<int> s(n + 1);
    for(int i = 1; i <= n; i++) {
        int x;
        cin >> x;
        s[i] = s[i - 1] + x;
    }

    const int bound = 20000 * n * 6;

    vector<int> mp(2 * bound + 1);
    ll all = 0;
    for(int i = 0; i <= n; i++) {
        for(int j = 0; j < n; j++) {
            for(int k = j + 1; k <= n; k++) {
                all += mp[s[k] - s[j] + s[i] + bound];
            }
        }

        for(int j = 0; j < n; j++) {
            for(int k = j + 1; k <= n; k++) {
                mp[s[j] - s[k] + s[i] + bound]++;
            }
        }
    }

    ll all_eq = 0;
    for(int i = 0; i < n; i++) {
        for(int j = i + 1; j <= n; j++) {
            if(s[j] == s[i]) all_eq++;
        }
    }

    for(int i = 0; i < mp.size(); i++) mp[i] = 0;
    ll two_eq = 0;
    for(int i = 0; i < n; i++) {
        for(int j = i + 1; j <= n; j++) {
            mp[s[j] - s[i] + bound]++;
        }
    }
    for(int i = 0; i < n; i++) {
        for(int j = i + 1; j <= n; j++) {
            ll x = 2 * (s[i] - s[j]) + bound;
            if(0 <= x && x < mp.size()) {
                two_eq += mp[x];
            }
        }
    }
    two_eq -= all_eq;

    ll ans = all - 3 * two_eq - all_eq;
    ans /= 6;
    cout << ans << endl;

    return 0;
}