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#include <bits/stdc++.h>
#define REP(i,n) for (int _n=(n), i=0;i<_n;++i)
#define FOR(i,a,b) for (int i=(a),_b=(b);i<=_b;++i)
#define FORD(i,a,b) for (int i=(a),_b=(b);i>=_b;--i)
#define TRACE(x) std::cerr << "TRACE(" #x ")" << std::endl;
#define DEBUG(x) std::cerr << #x << " = " << (x) << std::endl;

void init_io() {
  std::cin.tie(nullptr);
  std::ios::sync_with_stdio(false);
}

template<unsigned MOD>
class Modulo {
public:
  Modulo(unsigned x=0):v(x) {}
  unsigned get() const { return v; }
  Modulo operator+(Modulo b) const {
    unsigned res = v+b.v;
    if (res >= MOD) res -= MOD;
    return Modulo(res);
  }
  void operator+=(Modulo b) { *this = *this + b; }
  Modulo operator-(Modulo b) const { return *this + Modulo(MOD-b.v); }
  void operator-=(Modulo b) { *this = *this - b; }
  Modulo operator*(Modulo b) const { return Modulo(std::uint64_t(v) * b.v % MOD); }
  void operator*=(Modulo b) { *this = *this * b; }

  bool operator==(Modulo b) const { return v == b.v; }
  bool operator!=(Modulo b) const { return v != b.v; }
  bool operator<(Modulo b) const { return v < b.v; }
  bool operator>(Modulo b) const { return v > b.v; }
  bool operator<=(Modulo b) const { return v <= b.v; }
  bool operator>=(Modulo b) const { return v >= b.v; }

private:
  unsigned v;
};

template<class T>
class Fenwick {
public:
  explicit Fenwick(int n): tab(n+1) {}
  void Add(int p, const T &v);
  T Sum(int n) const;
  T SumAll() const { return sum_all; }
private:
  std::vector<T> tab;
  T sum_all{};
};

template<class T>
void Fenwick<T>::Add(int p, const T &v) {
  ++p;
  while(p < static_cast<int>(tab.size())) {
    tab[p] += v;
    p += (p & -p);
  }
  sum_all += v;
}

template<class T>
T Fenwick<T>::Sum(int n) const {
  T res = T();
  while(n) {
    res += tab[n];
    n &= (n-1);
  }
  return res;
}

using Mod = Modulo<1'000'000'007>;

std::vector<Mod> prefix_sums;
std::vector<Mod> unique_sums;

void read_prefix_sums() {
  int n; std::cin >> n;
  prefix_sums.reserve(n + 1);
  Mod sum {0};
  prefix_sums.push_back(sum);
  REP(i, n) {
    unsigned v;
    std::cin >> v;
    sum += Mod(v);
    prefix_sums.push_back(sum);
  }
}

void calc_unique_sums() {
  unique_sums = prefix_sums;
  std::sort(unique_sums.begin(), unique_sums.end());
  const auto it = std::unique(unique_sums.begin(), unique_sums.end());
  unique_sums.erase(it, unique_sums.end());
}

int find_index(const Mod x) {
  const auto it = std::lower_bound(unique_sums.begin(), unique_sums.end(), x);
  assert(it != unique_sums.end());
  assert(*it == x);
  return it - unique_sums.begin();
}

struct Elem {
  Mod ways[2] = {};

  void operator+=(const Elem &b) {
    ways[0] += b.ways[0];
    ways[1] += b.ways[1];
  }
};

Mod solve() {
  Fenwick<Elem> ways_table { int(unique_sums.size()) };
  Mod res{1};
  {
    Elem elem;
    elem.ways[0] = res;
    ways_table.Add(find_index(Mod(0)), elem);
  }
  for (auto it = prefix_sums.begin() + 1; it != prefix_sums.end(); ++it) {
    const Mod x = *it;
    const int index = find_index(x);
    const Elem small = ways_table.Sum(index+1);
    const Elem all = ways_table.SumAll();
    const unsigned parity = x.get() & 1;
    res = small.ways[parity] + all.ways[parity ^ 1] - small.ways[parity ^ 1];
    Elem new_elem;
    new_elem.ways[parity] = res;
    ways_table.Add(index, new_elem);
  }
  return res;
}

int main() {
  init_io();
  read_prefix_sums();
  calc_unique_sums();
  const Mod res = solve();
  std::cout << res.get() << '\n';
}