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#include <bits/stdc++.h>
using namespace std;
typedef complex<long double> cd;
const double PI = acos(-1);

void fft(vector<cd> & a, bool invert) {
    int n = a.size();

    for (int i = 1, j = 0; i < n; i++) {
        int bit = n >> 1;
        for (; j & bit; bit >>= 1)
            j ^= bit;
        j ^= bit;

        if (i < j)
            swap(a[i], a[j]);
    }

    for (int len = 2; len <= n; len <<= 1) {
        long double ang = 2 * PI / len * (invert ? -1 : 1);
        cd wlen(cos(ang), sin(ang));
        for (int i = 0; i < n; i += len) {
            cd w(1);
            for (int j = 0; j < len / 2; j++) {
                cd u = a[i+j], v = a[i+j+len/2] * w;
                a[i+j] = u + v;
                a[i+j+len/2] = u - v;
                w *= wlen;
            }
        }
    }

    if (invert) {
        for (cd & x : a)
            x /= n;
    }
}

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

    vector <int> A(n);
    for(auto &a: A) cin >> a;

    vector <int> S;
    int min_val = A[0], max_val = A[0];

    map <int, int> M;

    for(int i = 0; i<n; ++i){
        int sum = 0;

        for(int j = i; j<n; ++j){
            sum += A[j];
            S.push_back(sum);
            M[sum]++;

            min_val = min(min_val, sum);
            max_val = max(max_val, sum);
        }
    }

    long res = 0;

    res -= M[0]*M[0]*M[0] - M[0]*(M[0]-1)*(M[0]-2);
    
    for(auto m: M){
        if(m.first != 0){
            int y = -2*m.first;
            res -= 3*m.second*m.second*M[y];
            res += 3*m.second*(m.second-1)*M[y];
            //cout << "RES: " << res << " " << m.first << "\n";
        }
    }

    if(min_val > 0 || max_val < 0){
        cout << 0 << "\n";
        return 0;
    }

    int N = min(max_val - min_val + 1, -4*min_val + 1);

    for(int i = 0; i<=25; ++i){
        if(N <= (1<<i)){
            N = (1<<i);
            break;
        }
    }

    vector <cd> P(N);

    for(auto s: S){
        int act_s = s - min_val;
        if(act_s >= N) continue;
        P[act_s] = P[act_s] + (cd)1;
    }

    //for(auto p: P) cout << p << "\n";

    for(int i = 0; i<3*N; ++i){
        P.push_back(0);
    }

    fft(P, 0);
    vector <cd> Q(4*N);

    for(int i = 0; i<4*N; ++i){
        Q[i] = P[i]*P[i]*P[i];
    }

    fft(Q, 1);

    //for(auto q: Q) cout << q << " ";
    //cout << "\n";

    long long v = ceil(Q[-3*min_val].real());
    cout << (res + v)/6 << "\n";
}