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

vector<long long> dzielniki(long long n, int limit) {
    vector<long long> a, b;
    a.push_back(1);
    if (n <= limit) b.push_back(n);
    long long d = 2;
    while (d * d <= n && d <= limit) {
        if (n % d == 0) {
            a.push_back(d);
            long long e = n / d;
            if (e != d && e <= limit) {
                b.push_back(e);
            }
        }
        ++d;
    }
    // return b + reversed(a)
    vector<long long> res = b;
    for (int i = (int)a.size() - 1; i >= 0; --i)
        res.push_back(a[i]);
    return res;
}

bool test_d(long long d, const vector<long long> &a, long long suma, int n) {
    long long s = 0;
    long long k = 0;
    vector<long long> K(n + 1, 0);

    for (int i = 0; i <= n - (int)d; ++i) {
        k -= K[i];
        long long ak = a[i] - k;
        if (ak < 0) return false;
        k += ak;
        s += ak * d;
        K[i + d] = ak;
    }
    if (s != suma) return false;

    for (int i = n - (int)d + 1; i < n; ++i) {
        k -= K[i];
        long long ak = a[i] - k;
        if (ak != 0) return false;
    }
    return true;
}

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

    int n;
    if (!(cin >> n)) return 0;
    vector<long long> a(n);
    for (int i = 0; i < n; ++i) cin >> a[i];

    long long suma = 0;
    for (long long x : a) suma += x;

    vector<long long> D = dzielniki(suma, n);

    for (long long d : D) {
        if (test_d(d, a, suma, n)) {
            cout << d << "\n";
            break;
        }
    }
    return 0;
}