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#include <bits/stdc++.h>

#define pb push_back
#define st first
#define nd second

using namespace std;

typedef long long ll;
typedef pair<ll, ll> pll;

map<ll, ll> hashmap;

int main()
{
    ios_base::sync_with_stdio(0);
    ll n;
    cin >> n;
    vector<ll> v(n), sums(n+1, 0);
    for (int i = 0; i < n; ++i) {
        cin >> v[i];
        sums[i+1] = v[i] + sums[i];
    }

    vector<ll> prefs;
    for (int i = 0; i < n; ++i) {
        for (int j = i; j < n; ++j) {
            prefs.pb(sums[j+1] - sums[i]);
        }
    }

    ll result = 0;
    for (int i = 0; i < prefs.size(); ++i) {
        for (int j = i + 1; j < prefs.size(); ++j) {
            result += hashmap[- prefs[i] - prefs[j]];
        }
        hashmap[prefs[i]]++;
    }
    cout << result;
}