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#include <bits/stdc++.h>
#define FOR(i,n) for(int i = 0; i<n; ++i)
#define FOREACH(v, a) for(auto & v : (a))
#define X first
#define Y second
#define PR std::pair
#define MPR std::make_pair
typedef long long ll;
typedef std::vector<int> VI;

using namespace std;

#pragma region Ready functions

int fastPower(int a, int b){
    int res=1, pop_a = a;
    while(b){
        if(b&1) res *= pop_a;
        pop_a *= pop_a;
        b>>=1;
    }
    return res;
}

#pragma endregion

#define MOD 1000000007

ll wynik = 0;
vector<int> nums;
ll CountSubs[300003];

ll SmallValues(){

    vector<int> EvenNums;

    for(int v : nums){
        EvenNums.push_back(v%2);
    }

    int lastCn = 1;

    int howManyUnevens = 0;
    int howManyPairs = 0;

    for(int i = 0; i<EvenNums.size(); i++){
        if(EvenNums[i] == 0){ //we can just add to the previous results

            if(howManyUnevens%2==0){
                //cout<<i<<endl;
                lastCn *= 2;
                lastCn %= MOD;
            }

        }
        else{
            howManyUnevens++;
            if(howManyUnevens%2==0) {
                lastCn *= 2;
                lastCn %= MOD;
            }

        }
    }
    lastCn /= 2;

    if(howManyUnevens%2==1){
        return 0;
    }

    return lastCn;

}

//brut n^2

ll Brut(){


    for(int start = 0; start<nums.size(); start++){

        ll sum = 0;
        int currentWyn = 0;

        if(start == 0) currentWyn = 1;
        else if(CountSubs[start]==0) continue;
        else currentWyn = CountSubs[start];

        for(int wsk = start; wsk < nums.size(); wsk++){
            sum += nums[wsk];
            sum %= MOD;

            //cout<<start<<" "<<wsk<<" "<<currentWyn<<endl;
            
            if(sum%2==0){
                CountSubs[wsk+1] += currentWyn;
                CountSubs[wsk+1] %= MOD;
            }
        }
    }


    return CountSubs[nums.size()];

}


int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    

    int n;

    cin>>n;

    ll sumOfAll = 0;

    for(int i = 0; i<n; i++){
        int x;
        cin>>x;
        nums.push_back(x);
        sumOfAll+=x;
    }

    if(sumOfAll < MOD){
        wynik = SmallValues();
    }
    else{
        wynik = Brut();
    }

    cout<<wynik<<endl;
    
}