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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;
    cin >> n;

    vector<long long> a(n + 1);
    a[0] = 0;
    long long S = 0;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        S += a[i];
    }

    vector<long long> d(n + 1);
    for (int i = 1; i <= n; i++)
        d[i] = a[i] - a[i - 1];

    vector<int> candidates;
    for (long long div = 1; div * div <= S; div++) {
        if (S % div == 0) {
            if (div <= n) candidates.push_back((int)div);
            long long other = S / div;
            if (other != div && other <= n) candidates.push_back((int)other);
        }
    }
    sort(candidates.rbegin(), candidates.rend());

    vector<long long> x(n + 1);

    auto check = [&](int k) -> bool {
        for (int i = 1; i <= n; i++) {
            x[i] = d[i] + (i > k ? x[i - k] : 0LL);
            if (i <= n - k + 1) {
                if (x[i] < 0) return false;
            } else {
                if (x[i] != 0) return false;
            }
        }
        return true;
    };

    for (int k : candidates) {
        if (check(k)) {
            cout << k << "\n";
            return 0;
        }
    }

    return 0;
}