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//2024-03-16
//author: Marcin Rolbiecki
#include <bits/stdc++.h>
using namespace std;

const int maxN = 502;

int n, m;
int a[maxN];
vector <int> b {0};

unordered_map <int, int> cnt;
long long ans;

int main () {
		
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	
	cin >> n;
	for (int i = 1; i <= n; i++)
	{
		cin >> a[i];
	}
	for (int i = 1; i <= n; i++)
	{
		int sum = 0;
		for (int j = i; j <= n; j++)
		{
			sum += a[j];
			b.push_back(sum);
		}
	}
	
	m = b.size()-1;

	for (int j = m-1; j >= 1; j--)
	{
		cnt[b[j+1]]++;
		for (int i = j-1; i >= 1; i--)
		{
			ans += cnt[0-b[i]-b[j]];
		}
	}
	
	cout << ans;
	
	return 0;
}