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#include <bits/stdc++.h>

using namespace std;
using LL = long long;
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
#define ssize(x) int(x.size())

template<class A, class B> auto &operator<<(ostream &o, pair<A, B> p) {
    return o << '(' << p.first << ", " << p.second << ')';
}

template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) {
    o << '{'; int i = 0; for (auto e : x) o << (", ")+2*!i++ << e;
    return o << '}';
}

#ifdef DEBUG
#define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n';
#else
#define debug(...) {}
#endif


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

    int n;
    cin >> n;
    vector<int> a(n), started(n);
    LL total = 0;
    REP(i, n) {
        cin >> a[i];
        total += a[i];
    }

    int ans = 1;
    for (int k = n; k > 1; k--) {
        if (total % k != 0)
            continue;
        int current = 0;
        bool possible = true;
        REP(i, n) {
            if (i >= k)
                current -= started[i - k];
            if (current > a[i]) {
                possible = false;
                break;
            }
            started[i] = a[i] - current;
            current += started[i];
        }

        current -= started[n - k];
        if (current == 0 && possible) {
            ans = k;
            break;
        }
    }

    cout << ans << '\n';

    return 0;
}