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#ifdef NDEBUG
#undef LOCAL
#endif
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using ll   = long long;
using ull  = unsigned long long;
using ld   = long double;
using pii  = pair<int,int>;
using pll  = pair<ll,ll>;
using vi   = vector<int>;
using vb   = vector<bool>;
using vc   = vector<char>;
using vvc  = vector<vc>;
using vvi  = vector<vi>;
using vvb  = vector<vb>;
using vpii = vector<pii>;
using vpll = vector<pll>;
using vll  = vector<ll>;
using vull = vector<ull>;
using vvll = vector<vll>;
using namespace __gnu_pbds;
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define f first
#define s second
#define pb emplace_back
#define rep(i, begin, end) for(auto i = (begin); i <= (end); ++i)
#define repr(i, begin, end) for(auto i = (begin); i >= (end); --i)
#define bend(X) X.begin(), X.end()
constexpr int INF = 1e9+1e7;
constexpr ll INFl = INF;
constexpr ll INFll = 1e18+1e16;
#ifndef LOCAL
#define endl '\n'
#endif
template <typename T> void print(T x) { cout << x << endl; }
template <typename T, typename... Args> void print(T x, Args... args) { cout << x << ' '; print(args...); }
#ifdef LOCAL
template <typename T> void _deb(T x) { cout << x << endl; }
template <typename T, typename... Args> void _deb(T x, Args... args) { cout << x << ", "; _deb(args...); }
#define deb(...) do { cout << #__VA_ARGS__ << " = "; _deb(__VA_ARGS__); } while (false)
#define say(...) _deb(__VA_ARGS__);
template <typename T1, typename T2> ostream& operator<<(ostream& os, pair<T1,T2> x) { os << '(' << x.f << ", " << x.s << ')'; return os; }
template <typename Ch, typename Tr, typename T> ostream& operator<<(basic_ostream<Ch,Tr>& os, T x) { bool first = true; os << '['; for(auto i : x) { if (!first) os << ", "; os << i; first = false; } os << ']'; return os; }
#else
#define deb(...)
#define say(...)
template <typename T1, typename T2> ostream& operator<<(ostream& os, pair<T1,T2> x) { os << x.f << ' ' << x.s; return os; }
template <typename Ch, typename Tr, typename T> ostream& operator<<(basic_ostream<Ch,Tr>& os, T x) { for(auto i : x) os << i << ' '; return os; }
#endif
template <typename T1, typename T2> istream& operator>>(istream& is, pair<T1,T2>& x) { is >> x.f >> x.s; return is; }
template <typename T> istream& operator>>(istream& is, vector<T>& x) { for(T& i : x) is >> i; return is; }
template <typename T1, typename T2> pair<T1,T2> operator+(const pair<T1,T2>& A, const pair<T1,T2>& B) { return {A.f+B.f, A.s+B.s}; }
template <typename T1, typename T2> pair<T1,T2> operator-(const pair<T1,T2>& A, const pair<T1,T2>& B) { return {A.f-B.f, A.s-B.s}; }
template <typename T1, typename T2> pair<T1,T2>& operator+=(pair<T1,T2>& A, const pair<T1,T2>& B) { A.f += B.f; A.s += B.s; return A; }
template <typename T1, typename T2> pair<T1,T2>& operator-=(pair<T1,T2>& A, const pair<T1,T2>& B) { A.f -= B.f; A.s -= B.s; return A; }
template <typename T1, typename T2> pair<T1,T2> operator-(const pair<T1,T2>& A) { return {-A.f, -A.s}; }
template <typename T1, typename T2> bool maxe(T1& A, const T2& B) { if(B>A) { A=B; return 1; } return 0; }
template <typename T1, typename T2> bool mine(T1& A, const T2& B) { if(B<A) { A=B; return 1; } return 0; }
class Nic{} nic;
template <typename T> Nic operator<<(Nic, T) { return nic; }
Nic operator<<(ostream&, Nic) { return nic; }

template <typename T>
T fastpow(const T& x, const unsigned long long& p) {
    if (p == 1) return x;
    return (p&1) ? fastpow(x*x, p/2)*x : fastpow(x*x, p/2);
}
template <ll mod>
class nu {
private:
    ll v;
    // constructor called when you know v will be in [0,mod), so no modulo is performed
    nu(ll val, void* _) : v{val} {};

public:
    nu(ll val = 0) : v{val} {
        if (v >= mod || v <= -mod) v %= mod;
        if (v < 0) v += mod;
    };
    operator ll() { return v; }
    nu<mod> operator+(const nu<mod>& o) const { return nu<mod>{v+o.v >= mod ? v+o.v-mod : v+o.v, nullptr}; }
    nu<mod> operator-(const nu<mod>& o) const { return nu<mod>{v-o.v < 0 ? v-o.v+mod : v-o.v, nullptr}; }
    nu<mod> operator*(const nu<mod>& o) const { return nu<mod>{(v*o.v)%mod, nullptr}; }
    nu<mod> operator+=(const nu<mod>& o) { v += o.v; if (v >= mod) v -= mod; return *this; }
    nu<mod> operator-=(const nu<mod>& o) { v -= o.v; if (v < 0) v += mod; return *this; }
    nu<mod> operator*=(const nu<mod>& o) { v *= o.v; if (v >= mod) v %= mod; return *this; }
    // assumes mod is prime
    nu<mod> inv() const { return fastpow(*this, mod-2); }
    nu<mod> operator/(const nu<mod>& o) const { return (*this) * o.inv(); }
    nu<mod> operator/=(const nu<mod>& o) { v = ((*this)/o).v; return *this; }
    friend ostream& operator<<(ostream& os, const nu<mod>& x) { os << x.v; return os; }

    static vector<nu<mod>> all_inverses(size_t n) {
        vector<nu<mod>> inv(n+1);
        inv[1] = 1;
        for (int i = 2; i <= n; i++)
            inv[i] = nu<mod>(mod - (mod/i) * inv[mod%i] % mod, nullptr);
        return inv;
    }
    static vector<nu<mod>> all_inverses() {
        return all_inverses(mod-1);
    }
};
constexpr ll mod = 1e9+7;
using num = nu<mod>;

//////////////////////////////////////////////////

struct Tree {
    struct node {
        num x = 0;
        node* l = nullptr;
        node* r = nullptr;
    };
    node* root = nullptr;

    void add(node*& v, int l, int r, int a, const num& val) {
        if (v == nullptr) v = new node();
        v->x += val;
        if (l < r) {
            int m = (l+r)/2;
            if (a <= m) add(v->l, l, m, a, val);
            else        add(v->r, m+1, r, a, val);
        }
    }
    void add(int a, const num& val) {
        add(root, 0, mod-1, a, val);
    }
    num get(node* v, int l, int r, int L, int R) {
        if (v == nullptr || R < l || r < L) return num(0);
        if (L <= l && r <= R) return v->x;
        int m = (l+r)/2;
        return get(v->l, l, m, L, R) + get(v->r, m+1, r, L, R);
    }
    num get(int L, int R) {
        return L <= R ? get(root, 0, mod-1, L, R) : num(0);
    }
} Tr[2][2];

int n;
vi T;
vector<num> DP;

auto solve() {
    cin >> n;
    T.resize(n+1);
    DP.resize(n+1);
    rep (i, 1, n) {
        cin >> T[i];
    }
    DP[0] = 1;
    Tr[0][0].add(0, DP[0]);
    int reszta = 0;
    bool przekrecilo = 0;
    bool parzystosc = 0;
    rep (i, 1, n) {
        reszta += T[i];
        if (reszta >= mod) {
            przekrecilo = !przekrecilo;
            reszta -= mod;
        }
        if (T[i]%2)
            parzystosc = !parzystosc;
        deb(i);
        deb(reszta, przekrecilo, parzystosc);

        deb(Tr[0][0].get(0, mod-1));
        deb(Tr[0][1].get(0, mod-1));
        deb(Tr[1][0].get(0, mod-1));
        deb(Tr[1][1].get(0, mod-1));

        DP[i] += Tr[przekrecilo][parzystosc].get(0, reszta);
        DP[i] += Tr[!przekrecilo][!parzystosc].get(0, reszta);
        DP[i] += Tr[przekrecilo][!parzystosc].get(reszta+1, mod-1);
        DP[i] += Tr[!przekrecilo][parzystosc].get(reszta+1, mod-1);

        deb(DP[i]);

        Tr[przekrecilo][parzystosc].add(reszta, DP[i]);
    }

    return DP[n];
}



int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int noOfTests = 1;
    //cin >> noOfTests;

    while(noOfTests --> 0)
        cout << solve() << '\n';

    return 0;
}