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#include<iostream>
#include<vector>
#include<stack>
#include<queue>

using namespace std;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  long long n;
  cin >> n;
  vector<long long> amber(n);
  long long sum = 0;
  for(int i = 0; i < n; i++) {
    cin >> amber[i];
    sum += amber[i];
  }

  long long result = 1;
  stack<long long> candidates;
  stack<long long> higher_candidates;
  for(long long i = 1; i * i <= sum; i++) {
    if(sum % i == 0) {
      candidates.push(i);
      if(i*i != sum) {
        higher_candidates.push(sum / i);
      }
    }
  }
  while(!higher_candidates.empty()) {
    candidates.push(higher_candidates.top());
    higher_candidates.pop();
  }
  while (!candidates.empty()) {
    long long wave_length = candidates.top();
    candidates.pop();
    if(wave_length>n) {
      continue;
    }
    long long wave_count = 0;
    vector<long long> wave_start_counter(n, 0);
    for(long long i = 0; i < n; i++) {
      wave_start_counter[i]= amber[i] - wave_count;
      wave_count = amber[i];
      if(wave_start_counter[i] < 0) {
        wave_count = -1;
        break;
      }
      if(i >= wave_length-1) {
        wave_count -= wave_start_counter[i-wave_length+1];
      }
    }
    if(wave_count == 0) {
      result = wave_length;
      break;
    }
  }
  cout << result << endl;

}