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#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#define MAX 1000009
#define MOD 1000000007


long long a[MAX], pref[MAX], result[MAX];

long long smallHeuristic(int n) {
    pref[0] = a[0];
    for (int i=1; i<n; i++) {
        pref[i] = pref[i-1] + a[i];
    }
    
    if (pref[n-1] % 2) {
        return 0;
    }
    
    int divisionPoints = 0;
    
    for (int i=0; i<n-1; i++) {
        if (pref[i] % 2 == 0) divisionPoints++;
    }
    
    long long res = 1;
    while (divisionPoints--) res *= 2;
    return res;
}


long long quadHeuristic(int n) {
    result[0] = 1;
    for (int i=0; i<n; i++) {
        long long sum = a[i];
        for (int j=i; j>=0; j--) {
            if (sum % 2 == 0) {
                result[i+1] = (result[j] + result[i+1]) % MOD;
            }
            if (j) sum = (sum + a[j-1]) % MOD;
        }
    }
    
    return result[n];
}

long long sol(int n) {
    return quadHeuristic(n);
}

int main()
{
    int n;
    std::cin >> n;
    long long sum = 0;
    for (int i=0; i<n; i++) {
        std::cin >> a[i];
        sum += a[i]; 
    }
    
    long long result;
    if (n <= 3000) {
        result = quadHeuristic(n);
    } else if (sum < MOD) {
        result = smallHeuristic(n);
    } else {
        result = sol(n);
    }
    
    std::cout << result;
}