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/*
	Zadanie: Mopadulo
	Autor: Tomasz Kwiatkowski
*/

#include <bits/stdc++.h>

#define fi first
#define se second
#define pb push_back

using namespace std;
typedef long long ll;

const int MAXN = 3e5 + 7;
const int MOD = (int)1e9 + 7;

struct Node {
	Node *left, *right;
	long long sum;
	int a, b; // [a, b)

	Node (int A, int B) : a(A), b(B) {
		sum = 0;
		left = NULL;
		right = NULL;
	}

	bool is_leaf() {
		return a == b-1;
	}

	void insert(int ind, int val) {
		if ((ind < a) || (ind >= b))
			return;

		if (is_leaf()) {
			sum = (sum + val) % MOD;
			return;
		}

		if (left == NULL) {
			left = new Node(a, (a + b) / 2);
			right = new Node((a + b) / 2, b);
		}

		left->insert(ind, val);
		right->insert(ind, val);
		sum = (left->sum + right->sum) % MOD;
	}

	// [l, r]
	int get_sum(int l, int r) {
		if ((r < a) || (l >= b))
			return 0;

		if (((l <= a) && (b <= r)) || is_leaf())
			return sum;

		if (left == NULL) {
			left = new Node(a, (a + b) / 2);
			right = new Node((a + b) / 2, b);
		}

		return (left->get_sum(l, r) + right->get_sum(l, r)) % MOD;
	}
};

int main()
{
	ios_base::sync_with_stdio(0), cin.tie(0);
	
	int n;
	cin >> n;
	vector<int> arr(n);
	for (auto& a : arr)
		cin >> a;

	Node *evenRoot = new Node(0, 1<<30);
	Node *oddRoot = new Node(0, 1<<30);

	evenRoot->insert(0, 1);
	int sum = 0;
	int ans = 0;
	for (auto a : arr) {
		sum = (sum + a) % MOD;

		if (sum & 1) {
			int res = (evenRoot->get_sum(sum, MOD) + oddRoot->get_sum(0, sum)) % MOD;
			oddRoot->insert(sum, res);
			ans = res;
		}
		else {
			int res = (evenRoot->get_sum(0, sum) + oddRoot->get_sum(sum, MOD)) % MOD;
			evenRoot->insert(sum, res);
			ans = res;
		}
	}
	cout << ans << '\n';
	return 0;
}