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#include<bits/stdc++.h>
using namespace std;
long long n, t[1000005];
long long wyn;
vector<long long> v;
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n;
    for(int i = 0; i < n; i++)
    {
        cin >> t[i];
    }
    for(int L = 0; L < n; L++)
    {
        long long sum = t[L];
        v.push_back(t[L]);
        for(int P = L + 1; P < n; P++)
        {
            sum += t[P];
            v.push_back(sum);
        }
    }

    sort(v.begin(), v.end());

    while(v.size() > 2)
    {
        long long val = -v[v.size() - 1];
        v.pop_back();
        long long l = 0;
        long long p = v.size() - 1;
        while(l < p)
        {
            if(v[l] + v[p] > val) p--;
            else if(v[l] + v[p] < val) l++;
            else
            {
                if(v[l] != v[p])
                {
                    long long ilP = 1;
                    long long ilL = 1;
                    while(p > 0 && v[p - 1] == v[p])
                    {
                        p--;
                        ilP++;
                    }
                    p--;
                    while(l < v.size() && v[l + 1] == v[l])
                    {
                        l++;
                        ilL++;
                    }
                    l++;
                    wyn += ilP * ilL;
                }
                else
                {
                    long long ilP = 1;
                    while(p > 0 && v[p - 1] == v[p])
                    {
                        p--;
                        ilP++;
                    }
                    wyn += (ilP * (ilP - 1)) / 2;
                }
            }
        }
    }

    cout << wyn;
}