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//#pragma GCC optimize("Ofast", "unroll-loops")
//#pragma GCC target("sse", "sse2", "sse3", "ssse3", "sse4")

#include <bits/stdc++.h>

#define all(a) a.begin(),a.end()
#define len(a) (int)(a.size())
#define mp make_pair
#define pb push_back
#define fi first
#define se second

using namespace std;

typedef pair<int, int> pii;
typedef long long ll;
typedef long double ld;
template<class T>
using vec = vector<T>;

template<typename T>
bool umin(T &a, T b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}
template<typename T>
bool umax(T &a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

#ifdef KoRoVa
#define DEBUG for (bool _FLAG = true; _FLAG; _FLAG = false)
#define LOG(...) print(#__VA_ARGS__" ::", __VA_ARGS__) << endl
template <class ...Ts> auto &print(Ts ...ts) { return ((cerr << ts << " "), ...); }
#else
#define DEBUG while (false)
#define LOG(...)
#endif

const int max_n = -1, inf = 1000111222;



void test_case() {


}



int main() {
//    freopen("input.txt", "r", stdin);
//    freopen("output.txt", "w", stdout);

    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin >> n;
    vector <int> a(n);
    ll s = 0;
    for (auto &i : a) {
        cin >> i;
        s += i;
    }
    int ans = 1;
    vector <int> used(n + 1);

    auto can = [&] (int x) {
        LOG(x);
        vector <ll> can(n + 1);
        ll pref = 0;
        for (int i = 0; i < n; i++) {
            pref += can[i];
            ll val = a[i] - pref;
            if (val < 0) {
                return false;
            }
            if (val > 0) {
                int to = i + x;
                if (to > n) {
                    return false;
                }
                can[to] -= val;
                pref += val;
            }
        }
        pref += can[n];
        if (pref != 0) {
            return false;
        }
        return true;
    };
    for (int i = 2; i <= n; i++) {
        if (used[i]) {
            continue;
        }
        if (s % i == 0) {
            if (can(i)) {
                ans = i;
            }
            else {
                for (int j = i; j <= n; j += i) {
                    used[j] = 1;
                }
            }
        }
    }
    cout << ans << '\n';
}

/*
KoRoVa!
*/