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#include <bits/stdc++.h>
using namespace std;
using LL = long long;
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
#define ssize(x) int(x.size())
template<class A, class B> auto& operator<<(ostream &o, pair<A, B> p) {
    return o << '(' << p.first << ", " << p.second << ')';
}
template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) {
    o << '{'; int i = 0; for(auto e : x) o << (", ")+2*!i++ << e; return o << '}';
}
#ifdef DEBUG
#define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n'
#else
#define debug(...) {}
#endif

template<int mod>
struct modular {
	int val;
	modular() { val = 0; }
	modular(const LL& v) {
		val = int((-mod <= v && v <= mod) ? (int) v : v % mod);
		if(val < 0) val += mod;
	}
	int to_int() { return val; }

	friend ostream& operator<<(ostream &os, const modular &a) {
		return os << a.val;
	}
	friend istream& operator>>(istream &is, modular &a) {
		return is >> a.val;
	}

	friend bool operator==(const modular &a, const modular &b) {
		return a.val == b.val;
	}
	friend bool operator!=(const modular &a, const modular &b) {
		return !(a == b);
	}
	friend bool operator<(const modular &a, const modular &b) {
		return a.val < b.val;
	}
	friend bool operator<=(const modular &a, const modular &b) {
		return a.val <= b.val;
	}

	modular operator-() const { return modular(-val); }
	modular& operator+=(const modular &m) {
		if((val += m.val) >= mod) val -= mod;
		return *this;
	}
	modular& operator-=(const modular &m) {
		if((val -= m.val) < 0) val += mod;
		return *this;
	}
	modular& operator*=(const modular &m) {
		val = (LL) val * m.val % mod;
		return *this;
	}
	friend modular qpow(modular a, LL n) {
		if(n == 0) return 1;
		if(n % 2 == 1) return qpow(a, n - 1) * a;
		return qpow(a * a, n / 2);
	}
	friend modular inv(const modular &a) {
		assert(a != 0); return qpow(a, mod - 2);
	}
	modular& operator/=(const modular &m) { 
		return (*this) *= inv(m); 
	}
	modular operator++(int) {
		modular res = (*this);
		(*this) += 1;
		return res;
	}

	friend modular operator+(modular a, const modular &b) { return a += b; }
	friend modular operator-(modular a, const modular &b) { return a -= b; }
	friend modular operator*(modular a, const modular &b) { return a *= b; }
	friend modular operator/(modular a, const modular &b) { return a /= b; }
};
using mint = modular<int(1e9 + 7)>;
// using mint = modular<998244353>;

struct Fenwick {
    vector<mint> s;
    Fenwick(int n = 0) : s(n) {}
    void update(int pos, mint val) {
        for(; pos < ssize(s); pos |= pos + 1)
            s[pos] += val;
    }
    mint query(int pos) {
        mint ret = 0;
        for(pos++; pos > 0; pos &= pos - 1)
            ret += s[pos - 1];
        return ret;
    }
    mint query(int l, int r) {
        return query(r) - query(l - 1);
    }
};

int main() {
    cin.tie(0)->sync_with_stdio(0);

    int n;
    cin >> n;

    vector<int> a(n);
    REP(i, n) 
        cin >> a[i];

    mint sum = 0;
    vector<int> sums = {0};
    REP(i, n) {
        sum += a[i];
        sums.emplace_back(sum.to_int());
    }

    sort(sums.begin(), sums.end());
    auto scale = [&](mint x) {
        auto it = lower_bound(sums.begin(), sums.end(), x);
        return (int) distance(sums.begin(), it);
    };

    array trees = {
        Fenwick(n + 2),
        Fenwick(n + 2)
    };
    trees[0].update(0, 1);

    sum = 0;
    REP(i, n) {
        sum += a[i];

        int r = (sum.to_int() % 2);
        mint dp = trees[r].query(scale(sum)) 
                + trees[r ^ 1].query(scale(sum) + 1, n + 1);

        if(i == n - 1) {
            cout << dp << "\n";
            return 0;
        }

        trees[r].update(scale(sum), dp);
    }
}