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/*
 *  Copyright (C) 2021  Paweł Widera
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details:
 *  http://www.gnu.org/licenses/gpl.html
 */
#include <iostream>
#include <algorithm>
#include <vector>
#include <unordered_map>
using namespace std;


#define MOD 1000000007

int n, number;
vector<int> numbers;
unordered_map<int, int> cache;


int pow(int k) {
	long long int result = 1;
	for (int i = 0; i < k; ++i) {
		result = (2 * result) % MOD;
	}
	return result;
}


int check(int start) {
	vector<int> indices;
	indices.push_back(0);

	// find start index of all minimal subsets with even sum
	int sum = 0;
	for (int i = 0; i < n; ++i) {
		sum = (sum + numbers[i]) % MOD;
		if (sum % 2 == 0) {
			indices.push_back(i + 1);
			sum = 0;
		}
	}
	if (indices.back() != n) {
		return 0;
	}

	// simple case without overflows
	return pow(indices.size() - 2);
}


int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	cin >> n;
	numbers.reserve(n);
	cache.reserve(n + 1);

	for (int i = 0; i < n; ++i) {
		cin >> number;
		numbers.push_back(number);
	}

	cout << check(0) << endl;
	return 0;
}