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// Author : Jakub Rozek
// Task   : BUR – Bursztyny [C]
// Memory : n + D(S);
// Time   : n * D(S);

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

using ll = long long;

int n;
ll sum = 0;
vector<ll> start, a;
vector<int> dzielniki;   


bool check(int k) {
    ll active = 0, need;
    for (int i = 1; i <= n; ++i) {
        if (i - k >= 1) {
            active -= start[i - k];
        }
        if (i+k-1 <= n) {
            need = a[i] - active;
            if (need < 0) return false;
            start[i] = need;
            active += need;
        } else if (active != a[i]) {
            return false;
        }
    }
    return true;
};

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    cin >> n;
    start.resize(n+1);
    a.resize(n+1);
    
    for (int i=1; i<=n; ++i) {
        cin >> a[i];
        sum += a[i];
    }

    for (ll d=1; d*d<=sum; ++d) {
        if (sum % d != 0) continue;
        if (d <= n) {
            dzielniki.push_back((int)d);
        }
        ll d2 = sum / d;
        if (d2 != d && d2 <= n) {
            dzielniki.push_back((int)d2);
        }
    }

    sort(dzielniki.rbegin(), dzielniki.rend());

    for (int k : dzielniki) {
        if (check(k)) {
            cout << k << '\n';
            return 0;
        }
    }

    return 0;
}