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#include <iostream>
#include <map>
#include <stdint.h>
#include <vector>

const int64_t P = 1'000'000'007;

int g_result = 0;

void print(const std::vector<int> &v) {
  for (int i : v) {
    std::cerr << i;
  }
  std::cerr << std::endl;
}

bool next(std::vector<int> &partitions, std::vector<int> &maxes, int n) {
  int i = 0;

  ++partitions[i];

  while ((i < n - 1) && (partitions[i] > maxes[i] + 1)) {
    partitions[i] = 1;
    ++i;
    ++partitions[i];
  }

  if (i == n - 1) {
    return false;
  }

  int max = partitions[i];
  for (i = i - 1; i >= 0; --i) {
    maxes[i] = max;
  }

  return true;
}

void process(const std::vector<int64_t> &elements,
             const std::vector<int> &partition) {
  std::map<int, int64_t> m;

  for (size_t i = 0; i < elements.size(); ++i) {
    m[partition[i]] += elements[i];
  }

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

//  std::cerr << "-------------------" << std::endl;
//  for (const auto &[k, v] : m) {
//    std::cerr << v << " ";
//  }
//  std::cerr << "\n-------------------" << std::endl;

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

  for (auto [k, v] : m) {
    if ((v % P) % 2 != 0) {
      // DEBUG
//      std::cerr << "quit" << std::endl;

      return;
    }
  }

  g_result++;
}

int main() {
  int N = 0;
  std::cin >> N;

  std::vector<int64_t> v(N);

  for (int i = 0; i < N; ++i) {
    std::cin >> v[i];
  }

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

  std::vector<int> partitions(N, 1);
  std::vector<int> maxes(N, 1);

  process(v, partitions);

  while (next(partitions, maxes, N) == true) {
    process(v, partitions);
  }

  std::cout << g_result << std::endl;
  return 0;
}