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#include <bits/stdc++.h>
#define endl '\n'

using namespace std;
constexpr int maxN = 100'000;
long long nums[maxN], d[maxN + 1], dif[maxN + 1];
int n;

bool check(int k) {
   for (int i = 0; i < n; i++) {
      if (d[i] > 0) {
         if (i + k > n) return false; 
         d[i + k] += d[i];
      }
      else if (d[i] < 0) return false;
   }
   return (d[n] == 0);
}

int main() {
   ios_base::sync_with_stdio(false);
   cin.tie(nullptr);

   cin >> n;
   auto sz = (n + 1) * sizeof(long long);
   memset(d, 0, sizeof(d));
   memset(dif, 0, sizeof(dif));
   memset(nums, 0, sizeof(nums));

   long long sum = 0;
   for (int i = 0; i < n; i++) {
      cin >> nums[i];
      sum += nums[i];
   }
   dif[0] = nums[0]; dif[n] = -nums[n - 1];
   for (int i = 1; i < n; i++) dif[i] = nums[i] - nums[i - 1];

   for (long long v = (long long)n; v > 1; v--) {
      if (sum % v != 0) continue;
      memcpy(d, dif, sz);
      if (check(v)) {
         cout << v << endl;
         return 0;
      }
   }

   cout << 1 << endl;

   return 0;
}