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#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

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

    int n;
    if (!(cin >> n)) return 0;

    vector<long long> a(n + 2, 0);
    long long total_sum = 0;

    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        total_sum += a[i];
    }

    vector<long long> divisors;
    for (long long i = 1; i * i <= total_sum; i++) {
        if (total_sum % i == 0) {
            if (i <= n) {
                divisors.push_back(i);
            }
            long long other = total_sum / i;
            if (other != i && other <= n) {
                divisors.push_back(other);
            }
        }
    }

    sort(divisors.rbegin(), divisors.rend());

    vector<long long> x(n + 2, 0);

    for (long long k : divisors) {
        bool valid = true;

        for (int i = 1; i <= n + 1; i++) {
            long long diff = a[i] - a[i - 1];
            long long prev_x = (i > k) ? x[i - k] : 0;

            x[i] = diff + prev_x;

            if (i <= n - k + 1) {
                if (x[i] < 0) { 
                    valid = false;
                    break;
                }
            }
            else {
                if (x[i] != 0) { 
                    valid = false;
                    break;
                }
            }
        }

        if (valid) {
            cout << k << "\n";
            return 0;
        }
    }

    cout << 1 << "\n";
    return 0;
}