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#include <bits/stdc++.h>
using namespace std;
#define fwd(i, a, n) for (int i = (a); i < (n); i++)
#define rep(i, n)    fwd(i, 0, n)
#define all(X)       X.begin(), X.end()
#define sz(X)        int(size(X))
#define pb           push_back
#define eb           emplace_back
#define st           first
#define nd           second
using pii = pair<int, int>;
using vi = vector<int>;
using ll = long long;
using ld = long double;
#ifdef LOC
auto SS = signal(6, [](int) {
	*(int *)0 = 0;
});
#	define DTP(x, y)                                      \
		auto operator<<(auto &o, auto a)->decltype(y, o) { \
			o << "(";                                      \
			x;                                             \
			return o << ")";                               \
		}
DTP(o << a.st << ", " << a.nd, a.nd);
DTP(for (auto i : a) o << i << ", ", all(a));
void dump(auto... x) {
	((cerr << x << ", "), ...) << '\n';
}
#	define deb(x...) cerr << setw(4) << __LINE__ << ":[" #x "]: ", dump(x)
#else
#	define deb(...) 0
#endif

int32_t main() {
	cin.tie(0)->sync_with_stdio(0);
	int n;
	cin >> n;
	vector<ll> a(n);
	rep(i, n) cin >> a[i];
	ll sum = accumulate(all(a), 0LL);
	ll ans = 1;
	vector<ll> pref(n + 1);
	auto ok = [&](ll d) {
		fill(all(pref), 0);
		rep(i, n) {
			if (i > 0) {
				pref[i] += pref[i - 1];
			}
			if (pref[i] > a[i]) {
				return false;
			}
			ll diff = a[i] - pref[i];
			if (diff > 0) {
				pref[i] += diff;
				if (i + d <= n) {
					pref[i + d] -= diff;
				} else {
					return false;
				}
			}
		}
		return true;
	};
	for (ll d = 1; d * d <= sum; d++) {
		if (sum % d == 0) {
			if (ok(d))
				ans = max(ans, d);
			if (ok(sum / d))
				ans = max(ans, sum / d);
		}
	}
	cout << ans << '\n';
#ifdef LOCF
	cout.flush();
	cerr << "- - - - - - - - -\n";
	(void)!system(
		"grep VmPeak /proc/$PPID/status | sed s/....kB/\' MB\'/1 >&2"); // 4x.kB
																		// ....kB
#endif
	return 0;
}