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#include <bits/stdc++.h>
#include <math.h>
using namespace std;
#define endl "\n"
#define mp make_pair
#define st first
#define nd second
#define pii pair<int, int>
#define pb push_back
#define _upgrade ios_base::sync_with_stdio(0), cout.setf(ios::fixed), cout.precision(10), cin.tie(0), cout.tie(0);
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define fwd(i, a, b) for (int i = (a); i < (b); ++i)
#define trav(a, x) for (auto &a : x)
#define all(c) (c).begin(), (c).end()
#define sz(X) (int)((X).size())
typedef long double ld;
typedef unsigned long long ull;
typedef long long ll;
#ifdef LOCAL
ostream &operator<<(ostream &out, string str) {
   for (char c : str)
      out << c;
   return out;
}
template <class L, class R> ostream &operator<<(ostream &out, pair<L, R> p) { return out << "(" << p.st << ", " << p.nd << ")"; }
template <class L, class R, class S> ostream &operator<<(ostream &out, tuple<L, R, S> p) {
   auto &[a, b, c] = p;
   return out << "(" << a << ", " << b << ", " << c << ")";
}
template <class T> auto operator<<(ostream &out, T a) -> decltype(a.begin(), out) {
   out << '{';
   for (auto it = a.begin(); it != a.end(); it = next(it))
      out << (it != a.begin() ? ", " : "") << *it;
   return out << '}';
}
void dump() { cerr << "\n"; }
template <class T, class... Ts> void dump(T a, Ts... x) {
   cerr << a << ", ";
   dump(x...);
}
#define debug(...) cerr << "[" #__VA_ARGS__ "]: ", dump(__VA_ARGS__)
#else
#define debug(...) 42
#endif

#define int long long

const int mod = 1e9 + 7;

mt19937_64 gen(2137);
uniform_int_distribution<int> distr(0, mod - 1);
auto my_rand = bind(distr, gen); // my_rand() zwraca teraz liczbe z przedzialu [a, b]

#define r1 ((l + r) / 2) // ulatwia branie srodka przedzialu
#define l2 (r1 + 1)

struct SegmentTree { // drzewo przedzial-przedzial (add,sum)

   struct content {
      int mod;
      int sum;
   };

   vector<content> C;
   int size;

   SegmentTree(int x) { size = (1 << (32 - __builtin_clz(x))), C.resize(size * 2); } // drzewo przedzialowe dla zakresu [0,x),

   void add(int p, int q, int val, int l, int r, int wezel = 1) { // dodaje val do przedzialu [p,q]
      if (p > q)
         return;

      if (p == l && q == r) {
         C[wezel].mod += val;
         C[wezel].sum += (q - p + 1) * val;
         return;
      }

      add(p, min(r1, q), val, l, r1, 2 * wezel);
      add(max(l2, p), q, val, l2, r, 2 * wezel + 1);

      C[wezel].sum = C[2 * wezel].sum + C[2 * wezel + 1].sum + C[wezel].mod * (r - l + 1);
   }

   int query(int p, int q, int l, int r, int wezel = 1) { // suma na przedzial [p,q]
      if (p > q)
         return 0;

      if (p == l && q == r)
         return C[wezel].sum;

      return query(p, min(r1, q), l, r1, 2 * wezel) + query(max(l2, p), q, l2, r, 2 * wezel + 1) + C[wezel].mod * (q - p + 1);
   }

   void add(int p, int q, int val) { add(p, q, val, 0, size - 1); }
   int query(int p, int q) { return query(p, q, 0, size - 1); }
};

const int MAXN = 3e5 + 99;

SegmentTree tab[2] = {SegmentTree(MAXN + 10), SegmentTree(MAXN + 10)};

int32_t main() {
   _upgrade;
   int n = 3e5;
   cin >> n;
   vector<int> X(n);
   for (auto &x : X) {
      cin >> x;
   }

   rep(i, n - 1) X[i + 1] = (X[i + 1] + X[i]) % mod;

   set<int> U(all(X));
   U.insert(0);
   vector<int> T(all(U));

   tab[0].add(0, 0, 1);

   int wynik = -1;

   for (int x : X) {
      int r = x % 2;
      int idx = lower_bound(all(T), x) - T.begin();
      int res = tab[r].query(0, idx) + tab[r ^ 1].query(idx + 1, MAXN);
      res %= mod;
      wynik = res;
      tab[r].add(idx, idx, res);
   }

   cout << wynik << endl;
}