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#include <bits/stdc++.h>
using namespace std;
#define st first
#define nd second
#define ll long long


const ll maxn = 2e7 + 7, N = 1e7;
ll n, suma, ind, res;
ll tab[1000], t[maxn];
vector<int> v;

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n;
    for(int i = 1; i <= n; i++)
        cin >> tab[i];
    for(int i = 1; i <= n; i++){
        for(int j = i; j <= n; j++){
            suma += tab[j];
            t[suma + N]++;
        }
        suma = 0;
    }
    for(int i = -N; i <= N; i++){
        if(t[i + N] > 0)
            v.push_back(i);
    }
    for(int i = 0; i < v.size(); i++){
        for(int j = i; j < v.size(); j++){
            ind = -(v[i] + v[j]);
            if(v[j] <= ind){
                if(ind > N)
                    continue;
                if(i != j){
                    if(v[i] == ind)
                        res += ((t[v[i] + N] * (t[v[i] + N] - 1) / 2) * t[v[j] + N]);
                    else if(v[j] == ind)
                        res += ((t[v[j] + N] * (t[v[j] + N] - 1) / 2) * t[v[i] + N]);
                    else
                        res += (t[v[i] + N] * t[v[j] + N] * t[ind + N]);
                }
                else{
                    if(v[j] == ind) 
                        res+= ((t[v[i] + N] * (t[v[i] + N] - 1) * (t[v[i] + N] - 2)) / 6);
                    else
                        res += ((t[v[i] + N] * (t[v[i] + N] - 1)) / 2) * t[ind + N];
                }
            }
            else
                break;
        }
    }
    cout << res << '\n';
}