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


using ll = int64_t;

void solve() {
  int n = 0;
  cin >> n;

  vector<ll> vs(n);
  for(auto& v : vs) {
    cin >> v;
  }

  vector<ll> vs2 = vs;
  for(int i = 1; i < n; i++) {
    vs2[i] = vs[i] - vs[i - 1];
  }

  ll sum = accumulate(vs.begin(), vs.end(), 0ll);

  auto check = [&] (ll v) -> bool {
    for(int m = 0; m < v; m++) {
      ll sum = 0;
      ll add = 0;
      for(int i = m; i < n; i += v) {
        sum += vs2[i];
        if(vs2[i] + add < 0) {
          return false;
        }
        add = vs2[i] + add;
      }
      if(m != n % v) {
        if(sum != 0) {
          return false;
        }
      }
    }
    return true;
  };


  for(ll i = n; i >= 1; i--) {
    if(sum % i != 0) {
      continue;
    }
    if(check(i)) {
      cout << i;
      return;
    }
  }

}

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  //freopen("in", "r", stdin);
  solve();
}