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

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int n;
	cin >> n;
	vector<int> a(n + 1), pref(n + 1);
	FOR (i, 1, n) {
		cin >> a[i];
		pref[i] = pref[i - 1] + a[i];
	}
	const int Z = 40'000'100;
	vector<int> mp(Z * 2);
	LL ans = 0;
	FOR (i, 1, n) {
		FOR (l, 1, n)
			FOR (r, l, n)
				++mp[pref[r] - pref[l - 1] - pref[i - 1] + Z];
		FOR (l, 1, n)
			FOR (r, l, n)
				ans += mp[-(pref[r] - pref[l - 1] + pref[i]) + Z];
	}
	vector<int> single(Z * 2);
	FOR (l, 1, n)
		FOR (r, l, n)
			++single[pref[r] - pref[l - 1] + Z];
	FOR (l, 1, n)
		FOR (r, l, n)
			ans -= single[-(pref[r] - pref[l - 1]) * 2 + Z] * 3;
	ans += single[Z] * 2;
	assert(ans % 6 == 0);
	cout << ans / 6 << endl;
}