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#include <bits/stdc++.h>
using namespace std;

#ifdef D
#define DEBUG(x)        \
    do {                \
        x               \
        cout.flush();   \
    } while (0)
#else
#define DEBUG(x)
#endif

const long long M = 1e9 + 7;

int n, a, m, w;

int pot(long long a, int k) {
    if (k == -1) {
        return 0;
    }
    if (k == 0) {
        return 1;
    }
    if (k == 1) {
        return a;
    }
    if (k % 2 == 0) {
        long long b = pot(a, k / 2);
        return (b * b) % M;
    }
    return (a * pot(a, k - 1)) % M;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cin >> n;
    for (int i = 0; i < n; ++i) {
        cin >> a;
        if (a % 2 == m) {
            w++;
        } else {
            m = 1 - m;
        }
    }
    cout << pot(2, w - 1);
    return 0;
}