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#include <cstdio>
using namespace std;

int main() {
    int n, t, s = 0;
    bool p = true;
    scanf("%d", &n);
    for (int i=0;i<n;i++) {
        scanf("%d", &t);
        p ^= (t % 2 != 0);
        if (p) {
            if (s == 0) s = 1;
            else s = (s*2)%1000000007;
        }
    }
    if (!p) s = 0;
    printf("%d", s);
}