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#include <bits/stdc++.h>
using namespace std;

#define int long long

int n, ans;
int arr[507];

vector<int> v;

constexpr int MAXW = 1e7;

int ile[2*MAXW+7];

void init(){
	for(int i=1; i<=n; i++){
		int act = 0;
		for(int j=i; j<=n; j++){
			act += arr[j];
			v.push_back(act);
			ile[act+MAXW]++;
		}
	}
	sort(v.begin(), v.end());
}

set<tuple<int, int, int>> z;

signed main() {
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	
	cin >> n;
	
	for(int i=1; i<=n; i++) cin >> arr[i];
	
	init();
	
	for(int i=0; i<v.size()-2; i++){
		int a = v[i];
		int l = i+1, r = v.size()-1;
		while(l < r){
			int b = v[l], c = v[r];
			if(a+b+c > 0) r--;
			else if(a+b+c < 0) l++;
			else{
				z.insert(make_tuple(a,b,c));
				l++;
				r--;
			}
		}
	}
	
	for(auto i : z){
		int tmp = ile[get<0>(i)+MAXW]*ile[get<1>(i)+MAXW]*ile[get<2>(i)+MAXW];
		if(get<0>(i) == get<1>(i) && get<1>(i) == get<2>(i)){
			int x = ile[get<0>(i)+MAXW];
			tmp = x*(x-1LL)*(x-2LL)/6LL;
		}
		else if(get<0>(i) == get<1>(i)){
			int x = ile[get<0>(i)+MAXW];
			tmp = x*(x-1LL) * get<2>(i);
		}
		else if(get<1>(i) == get<2>(i)){
			int x = ile[get<1>(i)+MAXW];
			tmp = x*(x-1LL) * get<0>(i);
		}
		ans += tmp;
	}
	
	cout << ans << '\n';
	
	return 0;
}