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#include <iostream>
#include <vector>
#include <algorithm>
int n;
std::vector<long long> a;
std::vector<long long> pref;
std::vector<long long> res;
long long s;
int main(){
    std::ios_base::sync_with_stdio(0);

    std::cin>>n;
    long long sum=0;
    long long max=0;
    pref.emplace_back(0);
    for(int i=0;i<n ;i++){
        std::cin>>s;
        a.emplace_back(s);
        sum+=s;
        pref.emplace_back(sum);
        max=std::max(max,s);
    } 
    
    if(max*n<1000000007){
        //std::cerr<<"DD"<<std::endl;
        if(pref.back()%2==1){
            std::cout<<0<<std::endl;
            return 0;
        }
        long long res=1;
        for(int i=1;i<pref.size()-1;i++)
            if(pref[i]%2==0){
                res*=2;
                res%=1000000007;
            }
        
        std::cout<<res<<std::endl;
        return 0;
        
    }else{
    //if(n<=3000){
        res.emplace_back(1);
        for(int i=0;i<n;i++){
            long long act=0;
            for(int j=0;j<=i;j++)
                if(((pref[i+1]-pref[j])%(1000000007))%2==0)
                    act+=res[j];
            act%=1000000007;
            res.emplace_back(act);
        }
    //}
    
    }
        
    std::cout<<res.back()<<std::endl;
    

}