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

#ifdef LOCAL
#include "debug.cpp"
#else
#define debug(x...)
#endif

using ll = long long;

int main() {
    ll n;
    cin >> n;
    vector <ll> v(n);
    for (auto &x : v) cin >> x;

    auto check = [&](const ll x) -> bool {
        vector <ll> pref(n + 1, 0);
        vector <ll> tab = v;
        ll cur = 0;
        for (int i = 0; i < n; i++) {
            cur += pref[i];
            tab[i] -= cur;
            if (tab[i] > 0 && i + x <= n) {
                cur += tab[i];
                pref[i + x] -= tab[i];
                tab[i] = 0;
            }

            if (tab[i] != 0) return false;
        }
        return (*max_element(tab.begin(), tab.end()) == 0 && *min_element(tab.begin(), tab.end()) == 0);
    };

    set <ll> st;
    ll s = accumulate(v.begin(), v.end(), 0LL);
    for (ll i = 1; i * i <= s; i++) {
        if (s % i == 0) {
            if (i <= n) st.insert(i);
            if (s / i <= n) st.insert(s / i); 
        }
    }

    st.erase(1);
    vector <ll> to_try(st.rbegin(), st.rend());
    for (auto x : to_try) {
        if (check(x)) {
            cout << x << '\n';
            return 0;
        }
    }
    cout << 1 << '\n';
}