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#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
#include <cmath>
#include <unordered_map>
#include <string>
#include <queue>
#include <deque>
#include <set>
#include <cstdlib>
#include <ctime>
#include<chrono>
#include<thread>
#include<iomanip>
#include<fstream>
#define ll long long
#define pb push_back
#define mp make_pair
#define ff first
#define ss second

using namespace std;
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    ll n, mini = 1000000000000000;
    cin >> n;
    vector<ll> a;
    unordered_map<ll, ll> collector;
    for(int i = 0; i < n; i++) {
        int b;
        cin >> b;
        a.pb(b);
    }
    for(int i = 1; i < n; i++) {
        a[i] += a[i - 1];
    }
    for(int i = -1; i < n; i++) {
        for(int j = i + 1; j < n; j++) {
            if(i == -1) {
                collector[a[j]]++;
                mini = min(a[j], mini);
            }
            else {
                collector[a[j] - a[i]]++;
                mini = min(a[j] - a[i], mini);
            }
        }
    }
    auto it = collector.begin();
    ll count = 0, s = 0, l = 0;
    for(; it != collector.end(); it++) {
        for(auto it2 = it; it2 != collector.end(); it2++) {
            //if(-(it->first+it2->first) < mini) break;
            if(collector.count(-(it->first+it2->first))) {
                if(-(it->first+it2->first) != it->first && it->first != it2->first && -(it->first+it2->first) != it2->first) {
                    s += it->second * it2->second * collector[-(it->first+it2->first)];
                }
                else if(it->first == it2->first && it->first == -(it->first+it2->first)) {
                    count += (it->second * (it->second - 1) * (it->second - 2)) / 6;
                }
                else if(it->first == it2->first) {
                    l += (it->second * (it->second - 1) * collector[-(it->first+it2->first)]) / 2;
                }
                else if(it->first == -(it->first+it2->first)) {
                    l += (it->second * (it->second - 1) * it2->second) / 2;
                }
                else if(it2->first == -(it->first+it2->first)) {
                    l += (it2->second * (it2->second - 1) * it->second) / 2;
                }
            }
        }
    }
    count += s/3 + l/2;
    cout << count << endl;
    return 0;
}