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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int MAXN = 5e2 + 7;
const int MAX = 1e7 + 7;
const ll INF = 1e18;

int tab[MAXN];
//map<int, int> cnt;
int cntmin[MAX], cntmax[MAX];


void solve(){
	
	int n;
	cin >> n;
	
	for(int i = 1; i <= n; i++){
		
		cin >> tab[i];
	}
	
	vector<int> v;
	int ile0 = 0;
	
	for(int i = 1; i <= n; i++){
		
		int val = 0;
		
		for(int j = i; j <= n; j++){
			
			val += tab[j];
			if(val == 0) ile0++;
			else v.push_back(val);
		}
	}
	
	sort(v.begin(), v.end());
	
	for(int i = 0; i < v.size(); i++){
		
		if(v[i] < 0) cntmin[-v[i]]++;
		else cntmax[v[i]]++;
	}
	
	int zeroans = 0, ans = 0;
	zeroans += (ile0 * (ile0 - 1) * (ile0 - 2))/6;
	
	for(auto u : v){
		
		if(u > 0) break;
		if(cntmax[-u]) zeroans += ile0;	
	}
	
	for(int i = 0; i < v.size(); i++){
		
		for(int j = i + 1; j < v.size(); j++){
			
			int left = 0 - (v[i] + v[j]);
			int ile;
			if(left < 0) ile = cntmin[-left];
			else ile = cntmax[left];
			
			if(v[i] == left) ile--;
			if(v[j] == left) ile--;
			ans += ile; 	
		}
	}
	
	cout << zeroans + ans/3 << '\n';
	
}


signed main(){
	
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	
	int t = 1;
	//cin >> t;
	
	while(t--) solve();	
	
	return 0;
}