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#include<bits/stdc++.h>
#define FOR(i,a,b) for(int i=a;i<(int)b;++i)
#define FORD(i,a,b) for(int i=a;i>=(int)b;--i)
#define PB push_back
#define EB emplace_back
#define FI first
#define SE second
#define umap unordered_map
#define uset unordered_set
#define vi vector<int>
#define vvi vector<vi>
#define vll vector<ll>
#define vvll vector<vll>
#define vpii vector<pii>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define ALL(X) (X).begin(),(X).end()
#ifndef DEBUG
#define endl (char)10
#endif
using namespace std;
using ll = long long;
using ld = long double;

template <class T>
istream& operator>> (istream& is, vector<T>& vec){
    FOR(i,0,vec.size()) is >> vec[i];
    return is;
}
template <class T>
ostream& operator<< (ostream& os, vector<T>& vec){
    for(auto& t : vec) os << t << " ";
    return os;
}
template<class T, class U>
ostream& operator<< (ostream& os, const pair<T, U>& p){
    os << p.FI << " " << p.SE;
    return os;
}
template<class T, class U>
istream& operator>> (istream& is, pair<T, U>& p){
    is >> p.FI >> p.SE;
    return is;
}

const int MS = 10000000;
const int SS = 2 * MS + 5;

int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    vi VV(n);
    cin >> VV;
    vi co;
    vi licz(SS, 0);
    FOR(i,0,n) {
        int s = 0;
        FOR(j,i,n){
            s += VV[j];
            co.PB(s);
            licz[s + MS]++;
        }
    }
    sort(ALL(co));
    co.erase(unique(ALL(co)), co.end());
    ll ans = 0;
    FOR(i,0,co.size()){
        int x = co[i];
        ll mile = licz[x + MS];
        if(mile > 1){
            int v = -2 * x;
            int iv = v + MS;
            if (iv < 0) break;
            if (iv < SS) {
                if (licz[iv] > 0) {
                    ll p = mile;
                    p *= p - 1;
                    p /= 2;
                    if (x == 0) ans += (p * (mile - 2)) / 3;
                    else ans += p * licz[iv];
                }
            }
        }
        FOR(j,i+1,co.size()){
            int v = -(co[i] + co[j]);
            if (v <= co[j]) break;
            int iv = v + MS;
            if (iv < SS) {
                if (licz[iv] > 0) {
                    ll p = licz[co[i] + MS];
                    p *= licz[co[j] + MS];
                    ans += p * licz[iv];
                }
            }
        }
    }
    cout << ans << endl;
}