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#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;

const int N = 505;

int Original[N];
vector<ll> Numbers;
unordered_map<ll, int> Count;

ll Solve()
{
    ll sol = 0;
    for(int i = 0; i < Numbers.size(); i++) {
        for(int j = i+1; j < Numbers.size(); j++) {
            ll left = 0 - (Numbers[i] + Numbers[j]);
            sol += Count[left];
            sol -= (left == Numbers[i]) + (left == Numbers[j]);
        }
    }
    return sol/3;
}

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

    int n;
    cin >> n;

    for(int i = 0; i < n; i++) 
        cin >> Original[i];

    for(int i = 0; i < n; i++) {
        ll in = 0;
        for(int j = i; j < n; j++) {
            in += Original[j];
            Numbers.push_back(in);
            Count[in]++;
        }
    }
    cout << Solve();
}