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#include <iostream>
#include <vector>
#include <numeric>
#include <algorithm>

using namespace std;


bool check(int k, int n, const vector<int>& a) {
    if (k <= 0) return false;
    vector<long long> d(n + 2, 0);
    

    d[1] = a[0];
    for (int i = 1; i < n; ++i) {
        d[i + 1] = (long long)a[i] - a[i - 1];
    }
    d[n + 1] = -(long long)a[n - 1];


    for (int i = 1; i <= n - k + 1; ++i) {
        if (d[i] < 0) return false; 
        long long num_waves = d[i];
        d[i] -= num_waves;
        d[i + k] += num_waves;
    }

    for (int i = 1; i <= n + 1; ++i) {
        if (d[i] != 0) return false;
    }
    return true;
}

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

    int n;
    if (!(cin >> n)) return 0;

    vector<int> a(n);
    long long sum_a = 0;
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
        sum_a += a[i];
    }

    vector<int> candidates;
    for (long long i = 1; i * i <= sum_a; ++i) {
        if (sum_a % i == 0) {
            if (i <= n) candidates.push_back(i);
            if (sum_a / i <= n) candidates.push_back(sum_a / i);
        }
    }

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

    for (int k : candidates) {
        if (check(k, n, a)) {
            cout << k << endl;
            return 0;
        }
    }

    return 0;
}