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#include <bits/stdc++.h>
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize ("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

//szablon czesciowo skopiowany z profilu https://codeforces.com/profile/Geothermal
using namespace std;
 
typedef long long LL;
typedef long double LD;
 
typedef pair<int, int> pii;
typedef pair<LL,LL> pll;
typedef pair<LD,LD> pdd;
 
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<LD> vld;
typedef vector<LL> vll;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
 
template<class T> using pq = priority_queue<T>;
template<class T> using pqg = priority_queue<T, vector<T>, greater<T>>;
 
#define rep(i, a, b) for (int i=a; i<(b); i++)
#define repd(i,a,b) for (int i = (a); i >= b; i--)
#define sz(x) (int)(x).size()
#define pb push_back
#define st first
#define nd second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define memo(x) memset(x, 0, sizeof(x))
#define debug(x) cerr << x << " "
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
LL losuj(LL a, LL b){ return a+rng()%(b-a+1);}

const int mod = 1e9+7;

struct segtree{
	int size=1;
	vi t;
	
	void init(int n){
		while(size<n) size*=2;
		t.assign(2*size, 0);
	}
	//add na punkcie
	void add(int x, int val){
		x+=size;
		t[x] +=val;
		t[x] %=mod;
		while(x/2!=0){
			x/=2;
			t[x]+=val;
			t[x]%=mod;
		}
	}
	//suma na przedziale
	int query(int l, int r){
		l+=size-1;
		r+=size+1;
		int ans = 0;
		while(l/2!=r/2){
			if(l%2==0) ans+=t[l+1];
			if(r%2==1) ans+=t[r-1];
			l/=2;
			r/=2;
		}
		return ans;
	}
};

void solve(){
	int n; cin >> n;
	vll t(n+1,0), pref(n+1,0);
	map<int,int> skal;
	set<int>S;
	rep(i,1,n+1){
		cin >> t[i];
		pref[i] = (pref[i-1]+t[i])%mod;
		S.insert(pref[i]);
	}
	int tmp = 1;
	skal[0] = 0;
	for(auto x:S){
		skal[x] = tmp;
		tmp++;
	}
	// mapa <modulo, odpowiadająca liczba>
	vi dp(n+2,0);
	
	segtree p, np;
	p.init(n+2);
	np.init(n+2);
	p.add(0,1);
	rep(i,1,n){
		int cnt = 0, v = skal[pref[i]];
		if(pref[i]%2==0){
			cnt+=p.query(0,v) + np.query(v+1, n+1);
			p.add(v,cnt);
		}
		else{
			cnt+=np.query(0,v) + p.query(v+1,n+1);
			np.add(v,cnt);
		}
	}
	tmp = skal[pref[n]];
	if(pref[n]%2==0){
		cout << (p.query(0,tmp) + np.query(tmp+1,n+1))%mod << "\n";
	}
	else{
		cout << (np.query(0,tmp) + np.query(tmp+1,n+1) )%mod<< "\n";
	}
	
}

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	
	int t = 1;
	//cin >> t;
	while (t--) solve();
	
	return 0;
}