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#include<bits/stdc++.h>
using namespace std;

int main(){
    ios_base::sync_with_stdio(1);
    // cin.tie(0);

    int n;
    cin>>n;

    vector<int> w(n+1, 0);

    for(int i = 1; i <= n; i++){
        cin>>w[i];
        if(i){w[i]+=w[i-1];}
        // cout<<"D";
    }

    // cout<<"d\n";

    vector<pair<int, int>> s;
    map<int, int> m;

    // cout<<"d\n";

    for(int i = 1; i < n+1; i++){
        for(int j = 0; j < n-i+1; j++){
            m[w[j+i]-w[j]]++;
        }
    }

    for(auto v : m){
        s.push_back(v);
    }

    // cout<<"d\n";

    sort(s.begin(), s.end());

    // cout<<s.size()<<" d\n";

    int o = 0;

    for (int i = 0; i < s.size() - 2; i++) {
            int l = i + 1;
            int r = s.size() - 1;

            while (l < r) {
                if (s[i].first + s[l].first + s[r].first == 0) {
                    // cout<<s[i].first<<" "<<s[l].first<<" "<<s[r].first<<"\n";
                    o+=s[i].second*s[l].second*s[r].second;
                    r--;
                }
                else if (s[i].first + s[l].first + s[r].first < 0){
                    l++;
                }
                else{
                    r--;
                }
            }
        }

    cout<<o<<"\n";
}