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

const int N = int(3e5) + 99;

int n, x;
long long a[N];
long long b[N];
int input[N];
bool subtask = true;
const int p = 1e9+7;

void solve1() {
    a[0] = input[0];
    b[0] = (a[0] % 2 == 0) ? 1 : 0;
    for (int i = 1; i < n; i++) {
        x = input[i];
        b[i] = 0;

        if ((x + a[0])%p == 0) {
            b[i] = 1;   
        }

        for (int j = 1; j < i; j++) {
            if ((x + a[j]) % p == 0) {
                b[i] += b[j];
                b[i] %= p;
            } 
        }

        for (int j = 0; j <= i; j++) {
            a[j] += x;
            a[j] %= p;
        }
    }

    // for (int i = 0; i < n; i++) {
    //     cout << a[i] << " ";
    // }
    // cout << endl;

    // for (int i = 0; i < n; i++) {
    //     cout << b[i] << " ";
    // }
    // cout << endl;

    cout << b[n-1] << endl;
}

void solve2() {
    long long good = 0, bad = 0;
    long long temp;
    if (input[0] % 2 == 1) {
        bad++;
    } else {
        good++;
    }

    for (int i = 1; i < n; i++) {
        x = input[i];

        if (x % 2 == 1) {
            temp = good * 2;
            good = bad;
            bad = temp % p;
        } else {
            good = (good * 2) % p;
        }
    }
    cout << good << endl;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> input[i];
        if (input[i] > 3000) {
            subtask = false;
        }
    }

    if (subtask) {
        solve2();
    } else {
        solve1();
    }
}