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#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    
    int n;
    cin >> n;
    vector<int> tab(n*(n+1)/2+1, 0);
    for(int i = 1; i <= n; i++)
    {
        int tmp;
        cin >> tmp;
        tab[i] = tab[i-1]+tmp;
    }
    int p = n+1;
    ll ans = 0;
    for(int i = 1; i < n; i++)
    {
        for(int j = i+1; j <= n; j++)
        {
            tab[p++] = tab[j] - tab[i];
        }
    }
    for(int i = 1; i < n*(n+1)/2-1; i++)
    {
        for(int j = i+1; j < n*(n+1)/2; j++)
        {
            for(int k = j+1; k < n*(n+1)/2+1; k++)
            {
                if(tab[i] + tab[j] + tab[k] == 0)
                    ans++;
            }
        }
    }
    cout << ans << "\n";
    return 0;
}