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#include <algorithm>
#include <cstdint>
#include <vector>
#include <iostream>
using namespace std;

bool check(vector<int>& a, int k) {
    int n = a.size();
    vector<int> cur(n);
    for (int i = 0; i < n; i++) {
        if (i > 0) cur[i] += cur[i - 1];
        if (i + k - 1 < n) {
            int d = a[i] - cur[i];
            if (d < 0) return false;
            cur[i] += d;
            if (i + k < n) cur[i + k] -= d;
        }
    }
    for (int i = 0; i < n; i++) { 
        if (cur[i] != a[i]) return false;
    }
    return true;
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    
    int n; cin >> n;
    vector<int> a(n);
    int64_t sum = 0;
    for (int i = 0; i < n; i++) { 
        cin >> a[i];
        sum += a[i];
    }

    int res = 1;
    for (int64_t i = 1; i * i <= sum; i++) {
        if (i <= n && sum % i == 0 && check(a, i)) { 
            res = max(res, int(i));
        }
        if (sum / i <= n && sum % (sum / i) == 0 && check(a, sum / i)) { 
            res = max(res, int(sum / i));
        }
    }
    cout << res << '\n';
    return 0;
}
/*

4
1 0 1 2

8
1 2 3 4 5 5 3 1

*/