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

#define int long long
const int mod = 1e9+7;

void solve() {
    int n; cin >> n;
    vector<int>a(n);
    for (int i = 0; i < n; i++) cin >> a[i];
    int ss = accumulate(a.begin(), a.end(), 0ll);
    vector<int>divs;
    for (int i = 1; i * i <= ss; i++) {
        if (ss % i == 0) {
            divs.emplace_back(i);
            if (i * i != ss) divs.emplace_back(ss / i);
        }
    }
    vector<int>otwarte(n);
    int ans = 0;
    for (auto k: divs) {
        if (k > n) continue;
        // if (k != 3) continue;
        int s = 0;
        bool ok = 1;
        // cerr << k << "\n";
        for (int i = 0; i < n; i++) {
            if (i - k >= 0) {
                s -= otwarte[i - k];
            }
            if (s > a[i]) {
                ok = 0;
                break;
            }
            // cerr << a[i] - s << " ";
            otwarte[i] = a[i] - s;
            s += a[i] - s;            
        }
        // cerr << endl;
        if (ok == 1 && s == otwarte[n - k]) {
            ans = max(ans, k);
        }
    }
    cout << ans << endl;
}

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    solve();
}