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#include<bits/stdc++.h>      
using namespace std;
typedef long long ll;
const int P = 101;
const ll MLL = 1e18;
const ll LOG = 31;
const int N = 2e6;
unordered_map<int , ll> mp;
												
void solve() {
	
	int n;
	cin >> n;
	vector<int> all;
	vector<int> v(n);
	for(int i = 0; i < n; i++) cin >> v[i];
	for(int i = 0; i < n ;i++) {
		int sum = 0;
		for(int j = i; j < n ;j++) {
			sum += v[j];
			all.push_back(sum);
			if(mp.find(sum) == mp.end()) mp[sum] = 0;
			mp[sum]++;
		}
	}
	n = all.size();
	ll ans = 0;
	for(int i = 0; i < n; i++) {
		mp[all[i]]--;
		for(int j = i + 1; j < n; j++) {
			int sum = -(all[i] + all[j]);
			mp[all[j]]--;
			if(mp.find(sum) != mp.end()) {
				ans += mp[sum];
			}
		}
		for(int j = i + 1; j < n; j++) {
			mp[all[j]]++;
		}
	}
	cout << ans << endl;
}

int main()
{
	ios_base::sync_with_stdio(false);
    cin.tie(0);
    solve();


    return 0;
}