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#include<bits/stdc++.h>
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("trapv")

#define st first
#define nd second
#define pb(x) push_back(x)
#define pp(x) pop_back(x)
#define mp(a, b) make_pair(a, b)
#define all(x) (x).begin(), (x).end()
#define rev(x) reverse(all(x))
#define sor(x) sort(all(x))
#define sz(x) (int)(x).size()
#define rsz(x) resize(x)

using namespace std;

///~~~~~~~~~~~~~~~~~~~~~~~~~~

void debug(){cerr<<"\n";}
template <typename H, typename... T>
void debug(H h, T... t) {cerr<<h; if (sizeof...(t)) cerr << ", "; debug(t...);}
#define deb(x...) cerr<<#x<<" = ";debug(x);

///~~~~~~~~~~~~~~~~~~~~~~~~~

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii > vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef string str;

#define BOOST ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);

mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

const int N=3e5+5, INF=1e9+5, mod=1e9+7;
int tab[2][N+N];
void add(int t, int id, int val){
	for(id+=N; id>0; id>>=1){
		tab[t][id]+=val;
		tab[t][id]%=mod;
	}
}
int sum(int t, int l, int r){
	ll ans=0;
	for(l+=N, r+=N; l<r; l>>=1, r>>=1){
		if(l&1)ans+=tab[t][l++];
		if(r&1)ans+=tab[t][--r];
	}
	return ans%mod;
}
int main(){
	BOOST;
	int n;
	cin>>n;
	vl pref;
	pref.pb(0);
	for(int i=0; i<n; i++){
		int x;
		cin>>x;
		pref.pb((pref.back()+x)%(mod));
	}
	vl pref2=pref;
	sor(pref2);
	pref2.resize(unique(all(pref2))-pref2.begin());
	add(0, 0, 1);
	for(int i=1; i<=n; i++){
		ll dp=0;
		int k=lower_bound(all(pref2), pref[i])-pref2.begin();
		dp+=sum(pref[i]&1, 0, k+1);
		dp+=sum((pref[i]+1)&1, k+1, pref2.size());
		dp%=mod;
		add(pref[i]&1, k, dp);
		if(i==n)cout<<dp<<"\n";
	}
}