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/*
 * Opis: Główny nagłówek
 */
#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define st first
#define nd second
#define FOR(i,l,r)for(int i=(l);i<=(r);++i)
#define REP(i,n)FOR(i,0,(n)-1)
#define ssize(x)int(x.size())
#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<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

void brute(int n, vector<int> &tab) {

}

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int n;
	cin >> n;
	vector<int> tab(n);
	for (int &v : tab) {
		cin >> v;
	}
	vector<int> sums;
	REP(i, n) {
		int sum = 0;
		FOR(j, i, n-1) {
			sum += tab[j];
			sums.push_back(sum);
		}
	}
	sort(sums.begin(), sums.end());
	vector<pair<int, int> > merged;
	int curr = sums.front();
	int ile = 0;
	REP(i, ssize(sums)) {
		if (curr != sums[i]) {
			merged.push_back({curr, ile});
			curr = sums[i];
			ile = 0;
		}
		ile++;
	}
	merged.push_back({curr, ile});
	ile = 0;

	debug(ssize(merged));
	// debug(sums);
	// debug(merged);

	LL res = 0;
	FOR(i, 0, ssize(merged)) {
		int ptr = ssize(merged)-1;
		FOR(j, i, ssize(merged)-1) {
			if (merged[i].st + merged[j].st > 0) {
				break;
			}
			if (ptr < j) {
				break;
			}
			LL spos = merged[i].nd;
			if (j == i) {
				spos *= merged[j].nd - 1;
				spos /= 2;
			}
			else {
				spos *= merged[j].nd;
			}
			while (ptr > j && merged[i].st + merged[j].st + merged[ptr].st > 0) {
				ptr--;
			}
			if (merged[i].st + merged[j].st + merged[ptr].st == 0) {
				if (i == j && j == ptr) {
					spos *= merged[ptr].nd-2;
					spos /= 3;
				}
				else if (j == ptr) {
					spos *= merged[ptr].nd-1;
					spos /= 2;
				}
				else {
					spos *= merged[ptr].nd;
				}
				res += spos;
			}
		}
	}
	cout << res << "\n";
}