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#include <bits/stdc++.h>
using namespace std;

bool verify(int k, int offset, const vector<int>& arr) {
  long long cnt = 0;
  for (int i = offset; i < (int) arr.size(); i += k) {
    cnt += arr[i];
    if (cnt > 0) {
      return false;
    }
  }
  return cnt == 0;
}


bool first_check(int k, const vector<int>& arr) {
  static constexpr int T = 10;
  for (int t = 0; t < T; t++) {
    int a = rand() % k;
    if (!verify(k, a, arr)) {
      return false;
    }
  }
  return true;
}

bool last_check(int k, const vector<int>& arr) {
  for (int i = 0; i < k; i++) {
    if (!verify(k, i, arr)) {
      return false;
    }
  }
  return true;
}

int main() {
  srand(time(NULL));
  ios_base::sync_with_stdio(false);
  cin.tie(0);

  int n;
  cin >> n;
  vector<int> arr(n+1);

  long long sum_ = 0;
  for (int i = 1; i <= n; i++) {
    cin >> arr[i];
    sum_ += arr[i];
  }
  for (int i = 0; i < n; i++) {
    arr[i] -= arr[i+1];
  }
  for (int i = n; i >= 2; i--) {
    if (sum_ % i != 0) {
      continue;
    }
    if (!first_check(i, arr)) {
      continue;
    }
    if (last_check(i, arr)) {
      cout << i << "\n";
      return 0;
    }
  }
  cout << "1\n";
}