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// B3 - Mopadulo
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

#define MOD 1000000007;

struct Candidate {
	long long value;
	long long count;
	
	Candidate(long long v, long long c) {
		value = v;
		count = c;
	}
};

int main() {
	int n, a;
	long long good, almostGood, tmpGood, even;
	vector<long long> input;
	vector<Candidate> candidates;
	int candidatesSize;
	bool smallNumbers;
	
	cin >> n;
	smallNumbers = true;
	
	for (int i = 0; i < n; ++i) {
		cin >> a;
		input.push_back(a);
		if (a > 3333) {
			smallNumbers = false;
		}
	}
	
	if (smallNumbers) { 
		if (input[0] % 2) {
			good = 0;
			almostGood = 1;
		} else {
			good = 1;
			almostGood = 0;
		}
		for (int i = 1; i < n; ++i) {
			if (input[i] % 2) {
				tmpGood = good;
				good = almostGood;
				almostGood = (tmpGood + tmpGood) % MOD;
			} else {
				good = (good + good) % MOD;
				almostGood = almostGood;
			}
		}
		
		cout << good;
		return 0;
	}
	
	candidates.push_back(Candidate(input[0], 1));
	even = 1 - input[0] % 2;
	for (int i = 1; i < n; ++i) {
		candidatesSize = candidates.size();
		if (even > 0) {
			candidates.push_back(Candidate(input[i], even));
		}
		if (input[i] % 2) {
			even = 0;
		}
		
		for (int j = 0; j < candidatesSize; ++j) {
			candidates[j].value = (candidates[j].value + input[i]) % MOD;
			if (candidates[j].value % 2 == 0) {
				even = (even + candidates[j].count) % MOD;
			}
		}
	}
	
	cout << even << endl;	
	
	return 0;
}