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#include<bits/stdc++.h>
using namespace std;
#ifdef DEBUG
auto&operator <<(auto& o, pair<auto, auto> p) {return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator <<(auto& o, auto x)->decltype(x.end(), o) {o<<"{"; for(auto v : x) o<<v<<", "; return o<<"}";}
#define debug(X) cout<<"["#X"]"<<X<<endl;
#else
#define debug(X) {}
#endif
#define int long long
int32_t main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin>>n;
	vector<int> noms(n);
	for(auto& v : noms) cin>>v;
	int result = 0;
	vector<pair<int, int> > buc;
	unordered_map<int, int> ones;
	unordered_map<int, int> twos;
	for(int i=0;i<n;i++)
	{
		int sum = 0;
		for(int j=i;j<n;j++)
		{
			sum += noms[j];
			ones[sum]++;
		}
	}
	for(auto v : ones) buc.push_back(v);
	for(int i=0;i<buc.size();i++)
		for(int j=0;j<buc.size();j++)
		{
			if(i == j)
			{
				if(buc[i].first == 0) result-=2*buc[i].second*(buc[i].second-1);
				twos[buc[i].first+buc[i].first] += buc[i].second*(buc[i].second-1);
				continue;
			}
			if(buc[i].first*2+buc[j].first == 0) result-=buc[i].second*buc[j].second;
			if(buc[i].first+buc[j].first*2 == 0) result-=buc[i].second*buc[j].second;
			twos[buc[i].first+buc[j].first] += buc[i].second*buc[j].second;
		}
	for(auto v : ones)
		result += v.second*twos[-v.first];
	cout<<result/6;		
}