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#include<bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
typedef long long ll;
typedef pair<ll,ll> pll;
typedef pair<ll,int> pli;
typedef pair<int,ll> pil;
typedef pair<int,int> pii;
const ll INFLL=1e18+7;
const int INF=1e9+7;
#define pb push_back
const ll MOD=1e9+7;
const int NAX=3e5+7;
int n;
int arr[NAX];
int pref[NAX];
int dp[NAX];
int main()
{
	ios_base::sync_with_stdio(0);
	cin>>n;
	for(int i=1;i<=n;++i) cin>>arr[i];
	if(n<=3000){
		for(int i=1;i<=n;++i){
			pref[i]=pref[i-1]+arr[i];
			if(pref[i]>=MOD) pref[i]-=MOD;
		}
		for(int i=1;i<=n;++i){
			for(int j=1;j<i;++j){
				if(((pref[i]-pref[j]+MOD)%MOD)%2==0){
					dp[i]+=dp[j];
					if(dp[i]>=MOD) dp[i]-=MOD;
				}
			}
			if(pref[i]%2==0) ++dp[i];
			if(dp[i]>=MOD) dp[i]-=MOD;
		}
		//~ for(int i=1;i<=n;++i) cout<<dp[i]<<" ";
		cout<<dp[n]<<"\n";
	}else{
		int ans=1;
		for(int i=1;i<=n;++i) pref[i]=pref[i-1]+arr[i];
		int counter=0;
		for(int i=1;i<=n;++i) if(pref[i]%2==0) ++counter;
		for(int i=1;i<counter;++i){
			ans*=2;
			ans%=MOD;
		}
		if(counter==0||pref[n]%2==1) ans=0;
		cout<<ans<<"\n";
	}
}