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#include<bits/stdc++.h>
#define pb push_back
#define int long long
using namespace std;
const int mod=1e9+7, N=3e5+9;
//const int mod=1e2+7, N=3e5+9;
int n, tab[N], sumka, sumka_all, ile;
int32_t main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin>>n;
	for(int i=0; i<n; i++)
		cin>>tab[i];
	for(int i=0; i<n; i++){
		sumka=(sumka+tab[i])%mod;
		sumka_all=(sumka_all+tab[i])%mod;
		if(sumka%2==0){
			sumka=0;
			ile++;
		}
	}
	if(sumka_all%2==0){
		int potega=1;
		for(int i=0; i<ile-1; i++)
			potega=(potega*2)%mod;
		cout<<potega<<"\n";
	}
	else
		cout<<"0\n";
	return 0;
}