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#include <iostream>

const int maxN = 300 * 1000 + 20;
const long long mod = 1000 * 1000 * 1000 + 7;
const long long unsolved = -1;

int n;
long long a[maxN];
long long solution[maxN]; //number of solution to truncated problem

void start(){
        for(int i = 0; i < maxN; i++)
                solution[i] = unsolved;
}

long long solve(int ind){
        if(solution[ind] != unsolved)
                return solution[ind];
        long long answer = 0;
        long long sum = 0;
        for(int i = ind; i < n; i++){
                sum += a[i];
                sum %= mod;

                if(sum % 2 == 1) continue;

                if(i == n - 1)
                        answer += 1;
                else
                        answer += solve(i + 1);
                answer %= mod;
        }
        solution[ind] = answer;
        return answer;
}

int main(){

        std::cin >> n;
        for(int i = 0; i < n; i++)
                std::cin >> a[i];

        start();
        std::cout << solve(0) << "\n";

        return 0;
}