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// Patryk Jędrzejczak

#include <bits/stdc++.h>

using namespace std;

#define REP(i, n) for(int i = 0; i < n; ++i)
#define REPR(i, n) for(int i = n - 1; i >= 0; --i)
#define FOR(i, a, b) for(int i = a; i < b; ++i)
#define FORR(i, a, b) for(int i = b - 1; i >= a; --i)
#define EB emplace_back
#define MP make_pair
#define ST first
#define ND second
#define S size
#define RS resize
#define endl '\n'
#define L long long

template<class T> using V = vector<T>;

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

  int n;
  L mod = 1e9 + 7;
  cin >> n;

  V<L> a(n);
  L max_val = 0;
  REP(i, n) {
    cin >> a[i];
    max_val = max(max_val, a[i]);
  }

  V<L> sum(n);
  sum[0] = a[0];
  FOR(i, 1, n) {
    sum[i] = sum[i - 1] + a[i];
  }

  if (max_val <= 100) {
    V<V<L>> pref(n, V<L>(2));

    if (a[0] % 2 == 0) {
      pref[0][0] = 1;
    }

    FOR(i, 1, n) {
      if (a[i] % 2 == 0) {
        pref[i][0] = (pref[i - 1][0] * 2LL + (sum[i] % 2 == 0 ? 1LL : 0LL)) % mod;
        pref[i][1] = pref[i - 1][1];
      }
      else {
        pref[i][0] = (pref[i - 1][1] * 2LL + (sum[i] % 2 == 0 ? 1LL : 0LL)) % mod;
        pref[i][1] = pref[i - 1][0];
      }
    }

    L result = pref[n - 1][0];
    if (n > 1 && a[n - 1] % 2 == 0) {
      result = (result - pref[n - 2][0] + mod) % mod;
    }
    else if (n > 1) {
      result = (result - pref[n - 2][1] + mod) % mod;
    }
    cout << result << '\n';
  }
  else {
    V<L> dp(n);

    if (a[0] % 2 == 0) {
      dp[0] = 1;
    }

    FOR(i, 1, n) {
      REP(j, i) {
        L s = sum[i] - sum[j];
        if ((s % mod) % 2 == 0) {
          dp[i] += dp[j];
        }
      }
      if ((sum[i] % mod) % 2 == 0) {
        dp[i]++;
      }
      dp[i] %= mod;
    }
    cout << dp[n - 1] << '\n';
  }
}