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// 2021-3-mop-mopadulo.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include <map>
#include <algorithm>

constexpr long long MD = 1e9 + 7;
constexpr int MAXN = 1e6;
constexpr int DOD = 1 << 19;
constexpr int SIZ = 2 * DOD + 7;

long long prefsum[MAXN];
long long psstrd[MAXN];

void tree_incr(long long* t, int p, long long v)
{
	p += DOD;
	while (p > 0)
	{
		t[p] += v;
		t[p] = t[p] % MD;
		p /= 2;
	}
}

long long tree_get(long long* t, int b, int e)
{
	b += DOD;
	e += DOD;
	if (b == e)
	{
		return t[b];
	}
	long long answ = 0;
	answ += t[b];
	answ += t[e];
	answ %= MD;
	while (b/2 < e/2)
	{
		if (b%2 == 0)
		{
			answ += t[b + 1];
		}
		if (e%2 == 1)
		{
			answ += t[e - 1];
		}
		answ %= MD;
		b /= 2;
		e /= 2;
	}
	return answ % MD;
}

long long tr[2][SIZ];

long long hmend[MAXN];

int main()
{
	std::ios_base::sync_with_stdio(0);
	std::cin.tie(0);
	std::cout.tie(0);
	int n;
	long long l;
	std::cin >> n;
	std::map<long long, int> mp;
	for (size_t i = 1; i <= n; i++)
	{
		std::cin >> l;
		prefsum[i] = (prefsum[i - 1] + l) % MD;
		psstrd[i] = prefsum[i];
	}
	std::sort(psstrd, psstrd + n + 1);
	int cnt = 0;
	for (size_t i = 0; i <= n; i++)
	{
		if (mp.find(psstrd[i]) == mp.end())
		{
			cnt++;
			mp[psstrd[i]] = cnt;
		}
	}

	tree_incr(tr[0], mp[0ll], 1ll);
	for (size_t i = 1; i <= n; i++)
	{
		int tmp = mp[prefsum[i]];
		hmend[i] = tree_get(tr[prefsum[i] % 2], 0, tmp) + tree_get(tr[1 - (prefsum[i] % 2)], tmp, n+6);
		tree_incr(tr[prefsum[i] % 2], tmp, hmend[i]);
	}
	std::cout << hmend[n] % MD << '\n';
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started: 
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file