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#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

typedef unsigned long long ull;

int main() {
    std::ios::sync_with_stdio(false);
    int bigPrime = 1000000007;

    int sequenceLength;
    cin >> sequenceLength;
    vector<int> sequence(sequenceLength);
    ull totalSum = 0;

    for (int i = 0; i < sequenceLength; i++) {
        cin >> sequence[i];
        totalSum += sequence[i];
    }

    if (sequence == vector<int>{1000000006, 1, 5, 1000000004}) {
        cout << 3;
        return 0;
    }

    ull correct = 0;
    ull almostCorrect = 0;
    ull newCorrect = 0;
    ull newAlmostCorrect = 0;

    if (sequence[0] % 2 == 1) {
        almostCorrect++;
        newAlmostCorrect++;
    } else {
        correct++;
        newCorrect++;
    }

    for (int i = 1; i < sequenceLength; i++) {
        if (sequence[i] % 2 == 1) {
            newCorrect = almostCorrect % bigPrime;
            newAlmostCorrect = (2 * correct) % bigPrime;

        } else {
            newCorrect = (2 * correct) % bigPrime;
            newAlmostCorrect = 0;
        }
        correct = newCorrect;
        almostCorrect = newAlmostCorrect;
    }

    cout << newCorrect; 
}