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#include <bits/stdc++.h> //Michał Kuśmirek
using namespace std;     //XIII LO Szczecin

#define FOR(i, a, b) for(int i = (a); i <= (b); ++i)
#define REP(i, n) for(int i = 0; i < (n); ++i)

using ll = long long;
using pii = pair<int, int>;

template<class T> int size(T && a) {
	return (int)(a.size());
}
ostream& operator << (ostream &os, string str) {
    for(char c : str) os << c;
    return os;
}
template <class A, class B> ostream& operator << (ostream &os, const pair<A, B> &p) {
	return os << '(' << p.first << "," << p.second << ')';
}
template <class T> auto operator << (ostream &os, T &&x) -> decltype(x.begin(), os) {
	os << '{';
	for(auto it = x.begin(); it != x.end(); ++it)
		os << *it << (it == prev(x.end()) ? "" : " ");
	return os << '}';
}
template <class T> ostream& operator << (ostream &os, vector<vector<T>> vec) {
    for(auto x : vec)
    	os << "\n  " << x;
    return os;
}
void dump() {}
template <class T, class... Args> void dump(T &&x, Args... args) {
    cerr << x << "; ";
    dump(args...);
}
#ifdef DEBUG
# define debug(x...) cerr << "[" #x "]: ", dump(x), cerr << '\n'
#else 
# define debug(...) 0
#endif

//--------------------------------------------------

const int MOD = int(1e9) + 7;

int add(int a, int b) {
	if(a + b >= MOD)
		return a + b - MOD;
	return a + b;
}

struct SegmentTree { //add in point, sum on segment
	vector<int> T;
	int sz = 1;

	SegmentTree(int n) {
		while(sz < n)
			sz *= 2;
		T.resize(2 * sz);
	}

	void insert(int p, int val) {
		p += sz;
		T[p] = add(T[p], val);
		while(p /= 2)
			T[p] = add(T[p], val);
	}

	int sum(int l, int r) {
		if(l > r) return 0;

		l += sz, r += sz;
		int ret = T[l];
		if(l != r)
			ret = add(ret, T[r]);

		while(l / 2 != r / 2) {
			if(l % 2 == 0) ret = add(ret, T[l + 1]);
			if(r % 2 == 1) ret = add(ret, T[r - 1]);
			l /= 2, r /= 2;
		}

		return ret;
	}
};

vector<int> scale(vector<int> a) {
	int n = size(a);
	vector<pair<int, int>> vec(n);
	REP(i, n)
		vec[i] = pair(a[i], i);
	sort(vec.begin(), vec.end());

	int k = 0;
	REP(i, n) {
		if(i > 0 and vec[i].first > vec[i - 1].first)
			++k;
		a[vec[i].second] = k;
	}

	return a;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int n; cin >> n;
	vector<int> a(n), pref(n), overflow(n);
	REP(i, n) {
		cin >> a[i];
		pref[i] = a[i];
		if(i > 0) {
			overflow[i] = overflow[i - 1];
			pref[i] += pref[i - 1];
			if(pref[i] >= MOD) {
				++overflow[i];
				pref[i] -= MOD;
			}
		}
	}

	debug(pref);
	debug(overflow);

	vector<int> position = scale(pref);
	debug(position);

	vector<SegmentTree> tree(2, SegmentTree(n));
	vector<int> dp(n);

	REP(i, n) {
		int p = position[i];

		int par = pref[i] % 2;
		dp[i] = add(dp[i], tree[par].sum(0, p));
		dp[i] = add(dp[i], tree[par ^ 1].sum(p + 1, n - 1));
		if(par == 0)
			dp[i] = add(dp[i], 1);
		
		tree[par].insert(p, dp[i]);
	}

	debug(dp);

	cout << dp.back() << '\n';
}