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#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

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

    int n;
    cin >> n;
    vector<int> V(n), P{0};
    for (int &x : V) {
        cin >> x;
        P.push_back(P.back() + x);
    }

    vector<int> VV;
    VV.reserve(n*(n+1)/2);
    for (int i=0; i<n; i++)
        for (int j=i; j<n; j++)
            VV.push_back(P[j+1]-P[i]);
    sort(VV.begin(), VV.end());
    /* cerr << "VVsize = " << VV.size() << endl; */

    long long result = 0;
    for (int i=0; i<(int)VV.size(); i++) {
        int itL = i+1;
        int itR = (int)VV.size()-1;
        int cntL=1, cntR=1;
        while (itL < itR) {
            /* cerr << "i=" << i << " itL=" << itL << " itR=" << itR << endl; */
            if (VV[itL+1]==VV[itL]) {
                cntL++;
                itL++;
                continue;
            }
            if (VV[itR-1]==VV[itR]) {
                cntR++;
                itR--;
                continue;
            }

            int sum = VV[i] + VV[itL] + VV[itR];
            if (sum==0) {
                result += (long long)cntL*cntR;
                itL++;
                itR--;
                cntL = cntR = 1;
            }
            else if (sum < 0) {
                itL++;
                cntL = 1;
            }
            else {
                itR--;
                cntR = 1;
            }
        }
        if (itR>i && itL<(int)VV.size() && VV[itL]==VV[itR] && (VV[i]+VV[itL]+VV[itR]==0))
            result += (cntL + cntR - 1) * (cntL + cntR - 2) / 2;
    }
    cout << result << '\n';

    return 0;
}