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

#define pb push_back
#define fi first
#define sn second

typedef long long ll;
typedef vector<int> VI;
typedef vector<char> VC;
typedef pair<int, int> PI;

struct Factor {
    ll f;
    int cnt;
};

struct Wave {
    int width;
    int end;
};

void factorize(ll x, vector<Factor>& F) {
    Factor f;
    f.f = 2;
    f.cnt = 0;

    while ((x & 1) == 0) {
        x >>= 1;
        f.cnt++;
    }

    if (f.cnt > 0) {
        F.pb(f);
    }

    f.f = 3;
    f.cnt = 0;
    while (f.f * f.f <= x) {
        while (x % f.f == 0) {
            f.cnt++;
            x /= f.f;
        }
        if (f.cnt > 0) {
            F.pb(f);
        }

        f.f += 2;
        f.cnt = 0;
    }

    f.f = x;
    f.cnt = 1;
    if (f.cnt > 0) {
        F.pb(f);
    }
}

bool verify(int k, int n, VI& A) {
    queue<Wave> Q;
    int mod = 0;

    for (int i = 0; i < n; i++) {
        while (!Q.empty() && Q.front().end < i) {
            mod -= Q.front().width;
            Q.pop();
        }

        if (A[i] - mod > 0) {
            Wave w;
            w.width = A[i] - mod;
            w.end = i + k - 1;

            mod += w.width;
            Q.push(w);
        }
        else if (A[i] - mod < 0) {
            return false;
        }
    }

    while (!Q.empty() && Q.front().end < n) {
        mod -= Q.front().width;
        Q.pop();
    }

    return mod == 0;
}

int verify_over_all_divs(int k, int f, int n, VI& A, vector<Factor>& F) {
    if (k > n) {
        return 0;
    }
    if (f == F.size()) {
        return verify(k, n, A) ? k : 0;
    }

    int res = verify_over_all_divs(k, f + 1, n, A, F);
    int mul = 1;
    for (int i = 0; i < F[f].cnt; i++) {
        mul *= F[f].f;
        res = max(res, verify_over_all_divs(k * mul, f + 1, n, A, F));
    }

    return res;
}


int main() {
    int n;
    cin >> n;

    VI A(n);

    ll sum = 0; //99999992526;

    for (int i = 0; i < n; i++) {
        cin >> A[i];
        sum += A[i];
    }

    vector<Factor> factors;

    factorize(sum, factors);

    int res = max(1, verify_over_all_divs(1, 0, n, A, factors));

    cout << res << endl;

#ifdef DEBUG
    cout << sum << endl;
    for (int i = 0; i < factors.size(); i++) {
        cout << factors[i].f << " " << factors[i].cnt << endl;
    }
#endif 

    return 0;
}