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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 << ")"; }
auto operator<<(auto &o, auto a) -> decltype(all(a), o);
DTP(o << a.st << ", " << a.nd, a.nd);
DTP(for (auto i : a) o << i << ", ", all(a));
#define deb(x...) cerr << setw(4) << __LINE__ << ":[" #x "]: ", [](auto... arg_) { (( cerr << arg_ << ", " ), ...) << '\n'; }(x)
#else
#define deb(...) 0
#endif

bool div(vector<ll> a, int k) {

    rep(i, sz(a)) if (a[i]) {
        if (a[i] > 0) return false;
        if (i+k >= sz(a)) return false;
        a[i+k] += a[i];
    }
    return true;
}

int32_t main() {
    int n;
    cin >> n;
    vector<ll> a(n);
    rep(i, n) cin >> a[i];

    ll sa = accumulate(all(a), 0LL);
    a.pb(0);
    for (int i = sz(a)-1; i >= 0; --i) {
        a[i] = -a[i];
        if (i) a[i] += a[i-1];
    }

    deb(a, sa);

    for (int i = n; i; --i) if (sa % i == 0) {
        if (div(a, i)) {
            cout << i << '\n';
            return 0;
        }
    }
    assert(false);
}