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#pragma GCC optimize ("Ofast")
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define FOR(i, a, b) for (auto i=(a); i<(b); i++)
#define FORD(i, a, b) for (int i=(a); i>(b); i--)
#define SZ(x) ((int)(x).size())
#define ALL(x) (x).begin(), (x).end()
#define PPC(x) __builtin_popcountll(x)
#define MSB(x) (63 - __builtin_clzll(x))
#define LSB(x) __builtin_ctzll(x)
#define ARG(x, i) (get<i>(x))
#define ithBit(m, i) ((m) >> (i) & 1)
#define pb push_back
#define ft first
#define sd second
#define kw(a) ((a) * (a))
#define CLR(x) x.clear(), x.shrink_to_fit()
#ifdef DEBUG
#include "debug.h"
#else
#define dbg(...) 0
#endif
using namespace std;
 
template <typename T1, typename T2> inline void remin(T1& a, T2 b) { a = min(a, (T1)b);	}
template <typename T1, typename T2> inline void remax(T1& a, T2 b) { a = max(a, (T1)b);	}

const int maxN = 1 << 9;

map <int, int> pos, neg;
int T[maxN];

long long npo2(long long n)
{
	return n * (n-1) / 2;
}

long long npo3(long long n)
{
	return n * (n-1) * (n-2) / 6;
}

long long findCustom(const auto& M, int k)
{
	auto it = M.find(k);
	return it == M.end()
		? 0
		: it->sd;
}

long long f(const auto& A, const auto& B)
{
	long long ret = 0;

	for (auto it = A.begin(); it != A.end(); it++)
	{
		for (auto jt = A.begin(); jt != it; jt++)
			ret += findCustom(B, it->ft + jt->ft) * it->sd * jt->sd;

		ret += findCustom(B, it->ft * 2) * npo2(it->sd);
	}
		
	return ret;
}

void solve()
{
	int n;
	scanf ("%d", &n);
	
	FOR(i, 1, n+1)
		scanf ("%d", T+i);

	int zeros = 0;

	FOR(i, 1, n+1)
	{
		int s = 0;
		FOR(j, i, n+1)
		{
			s += T[j];
			if (s < 0)
				neg[-s]++;
			if (s == 0)
				zeros++;
			if (s > 0)
				pos[s]++;
		}
	}

	long long res = npo3(zeros);

	for (auto& [s, cnt] : pos)
		res += findCustom(neg, s) * zeros * cnt;

	res += f(pos, neg);
	res += f(neg, pos);


	printf("%lld\n", res);

//	check(n, res);
}

int main()
{
	int t = 1;
//	scanf ("%d", &t);	
	FOR(tid, 1, t+1)
	{
		//printf("Case #%d: ", tid);
		solve();
	}
	return 0;
}