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#include <bits/stdc++.h>
#define boost ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define debug(x) cerr << #x << " " << x << endl
#define int long long
#define st first
#define nd second

using namespace std;

const int N(3e5 + 13);
const int MAX(LLONG_MAX);
const int MOD(1e9+7);

int n, cnt_0;
int arr[N], sumpref[N];
bool flag;
string s;

int32_t main() {
  boost;
  cin >> n;
  for (int i = 1; i <= n;i++) {
    cin >> arr[i];
    arr[i] %= 2;
    sumpref[i] = (sumpref[i - 1] + arr[i]) % 2;
    if(sumpref[i] == 0) {
      cnt_0++;
    }
  }

  if(sumpref[n] == 1) {
    cout << 0;
  } else {
    cout << (1 << (cnt_0 - 1));
  }

  cout << endl;
  
}