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#include <bits/stdc++.h>
#define ll long long
using namespace std;

const int MAX = 300005;
const ll q = 1000000007, q2 = 2 * q, Q = q * q;

int n;
ll A[MAX], D[MAX];


template <typename T>
ostream & operator << (ostream &out, const vector <T> &V) {
	if (!V.empty()) {
		out << "{";
		for (auto v : V)
			out << v << ", ";
		out << "\b\b}";			// \b is backspace
	}
	else {
		out << "{}";
	}
	return out;
}

template <class T1, class T2>
ostream & operator << (ostream &out, const pair <T1, T2> &P) {
	out << "{" << P.first << ", " << P.second << "}";
	return out;
}


void testcase_sum_less_than_q() {
	ll C[2] = {0, 0};
	D[0] = 1;
	C[0] += D[0];
	D[1] = 1 - (A[1] & 1);
	C[(A[1] & 1)] += D[1];
	ll cur_par = A[1] & 1;
	for (int i = 2; i <= n; i++) {
		cur_par = (cur_par + A[i]) & 1;
		D[i] = C[cur_par];
		C[cur_par] += D[i];
		if (C[cur_par] >= Q) {
			C[cur_par] %= q;
		}
	}
	cout << D[n] % q <<endl;
}

void testcase_n_less_than_3000() {
	D[0] = 1;
	D[1] = 1 - (A[1] & 1);
	for (int i = 2; i <= n; i++) {
		ll sum = A[i];
		for (int j = i-1; j >= 0; j--) {
			if (((sum % q) & 1) == 0) {
				D[i] += D[j];
			}
			sum += A[j];
		}
		D[i] %= q;
	}
	cout << D[n] % q <<endl;
}




void update(int l, int r, int b, int e, ll v, vector <ll> &Tree) {
	if (e <= l || r <= b) {
	}
	else if (l <= b && e <= r) {
		Tree[b+e] += v;
	}
	else {
		int be = (b+e)/2;
		update(l, r, b, be, v, Tree);
		update(l, r, be, e, v, Tree);
		Tree[b+e] = Tree[b+be] + Tree[be+e];
	}
}


ll query(int l, int r, int b, int e, vector <ll> &Tree) {
	if (e <= l || r <= b) {
		return 0;
	}
	else if (l <= b && e <= r) {
		return Tree[b+e];
	}
	else {
		int be = (b+e)/2;
		return query(l, r, b, be, Tree) + query(l, r, be, e, Tree);
	}
}


inline int get_cat(int val) {
	return (val < q) ? (val & 1) : (3 - (val & 1));
}


inline int get_pos(int val, vector <ll> &SP) {
	return lower_bound(SP.begin(), SP.end(), val) - SP.begin();
}


void testcase_all() {
	vector <ll> Pref(n+1), Sorted_prefs[4];
	Pref[0] = 0;
	Sorted_prefs[get_cat(0)].push_back(0);
	for (int i = 1; i <= n; i++) {
		Pref[i] = (Pref[i-1] + A[i]) % q2;
		Sorted_prefs[get_cat(Pref[i])].push_back(Pref[i]);
	}
	Sorted_prefs[0].push_back(0);
	Sorted_prefs[0].push_back(q-1);
	Sorted_prefs[1].push_back(1);
	Sorted_prefs[1].push_back(q-2);
	Sorted_prefs[2].push_back(q);
	Sorted_prefs[2].push_back(q2-1);
	Sorted_prefs[3].push_back(q+1);
	Sorted_prefs[3].push_back(q2-2);
	int s = 1;
	for ( ; s < 2 * (n+4); s *= 2);
	vector <ll> Tree[4];
	for (int c = 0; c < 4; c++) {
		sort(Sorted_prefs[c].begin(), Sorted_prefs[c].end());
		Tree[c].resize(s, 0);
		// cerr << c << ": " << Sorted_prefs[c] <<endl;
	}
	int v = 0, c = get_cat(v), p = get_pos(v, Sorted_prefs[c]);
	D[v] = 1;
	update(p, +1, 0, s/2, D[v], Tree[c]);
	
	for (int i = 1; i <= n; i++) {
		int v = Pref[i], c = get_cat(v), p = get_pos(v, Sorted_prefs[c]);
		D[i] = 0;
		if (c == 0) {		// 0 <= v < q,  v % 2 == 0
			D[i] += query(0, p+1, 0, s/2, Tree[c]);
			int c2 = 3-c, v2 = q2+v-(q-1), p2 = get_pos(v2, Sorted_prefs[c2]);
			D[i] += query(p2, s/2, 0, s/2, Tree[c2]);
			int c3 = 1-c, v3 = v+1, p3 = get_pos(v3, Sorted_prefs[c3]);
			D[i] += query(p3, s/2, 0, s/2, Tree[c3]);
			int c4 = 2+c, v4 = v+q, p4 = get_pos(v4, Sorted_prefs[c4]);
			while (0 <= p4 && Sorted_prefs[c4][p4] > v+q) p4--;
			D[i] += query(0, p4+1, 0, s/2, Tree[c4]);
		}
		else if (c == 1) {		// o <= v < q,  v % 2 == 1
			D[i] += query(0, p+1, 0, s/2, Tree[c]);
			int c2 = 3-c, v2 = q2+v-(q-1), p2 = get_pos(v2, Sorted_prefs[c2]);
			D[i] += query(p2, s/2, 0, s/2, Tree[c2]);
			int c3 = 1-c, v3 = v+1, p3 = get_pos(v3, Sorted_prefs[c3]);
			D[i] += query(p3, s/2, 0, s/2, Tree[c3]);
			int c4 = 2+c, v4 = v+q, p4 = get_pos(v4, Sorted_prefs[c4]);
			while (0 <= p4 && Sorted_prefs[c4][p4] > v+q) p4--;
			D[i] += query(0, p4+1, 0, s/2, Tree[c4]);
		}
		else if (c == 2) {		// q <= v < 2q,  v % 2 == 1
			D[i] += query(0, p+1, 0, s/2, Tree[c]);
			int c2 = 3-c, v2 = v-(q-1), p2 = get_pos(v2, Sorted_prefs[c2]);
			D[i] += query(p2, s/2, 0, s/2, Tree[c2]);
			int c3 = 5-c, v3 = v+1, p3 = get_pos(v3, Sorted_prefs[c3]);
			D[i] += query(p3, s/2, 0, s/2, Tree[c3]);
			int c4 = c-2, v4 = v-q, p4 = get_pos(v4, Sorted_prefs[c4]);
			while (0 <= p4 && Sorted_prefs[c4][p4] > v-q) p4--;
			D[i] += query(0, p4+1, 0, s/2, Tree[c4]);
		}
		else {					// q <= v < 2q,  v % 2 == 0
			D[i] += query(0, p+1, 0, s/2, Tree[c]);
			int c2 = 3-c, v2 = v-(q-1), p2 = get_pos(v2, Sorted_prefs[c2]);
			D[i] += query(p2, s/2, 0, s/2, Tree[c2]);
			int c3 = 5-c, v3 = v+1, p3 = get_pos(v3, Sorted_prefs[c3]);
			D[i] += query(p3, s/2, 0, s/2, Tree[c3]);
			int c4 = c-2, v4 = v-q, p4 = get_pos(v4, Sorted_prefs[c4]);
			while (0 <= p4 && Sorted_prefs[c4][p4] > v-q) p4--;
			D[i] += query(0, p4+1, 0, s/2, Tree[c4]);
		}
		D[i] %= q;
		update(p, p+1, 0, s/2, D[i], Tree[c]);
		// cerr << i << " v=" << v << " c=" << c << " p=" << p << " | " << " _ " << D[i] <<endl;
	}
	
	cout << D[n] % q <<endl;
}


int main() 
{
	ios_base::sync_with_stdio(false);
	cin >> n;
	ll sum = 0;
	for (int i = 1; i <= n; i++) {
		cin >> A[i];
		sum += A[i];
	}
	/*if (sum < q) {
		testcase_sum_less_than_q();
	}
	else 
	*/
	if (n <= 3000) {
		testcase_n_less_than_3000();
	}
	else {
		testcase_all();
	}
	return 0;
}