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

bool can_reduce_to_zero(const vector<long long>& arr, int k) {
    int n = (int)arr.size();
    if (n == 0) {
        return true;
    }

    vector<long long> diff(n + 1, 0);
    long long active_sub = 0;

    for (int i = 0; i < n; i++) {
        active_sub -= diff[i];

        long long current = arr[i] - active_sub;

        if (current < 0) {
            return false;
        }

        if (i <= n - k) {
            long long x = current;
            active_sub += x;
            diff[i + k] += x;
        } else {
            if (current != 0) {
                return false;
            }
        }
    }

    return true;
}

int main() {
    int n;
    cin >> n;
    long long s=0;
    vector<long long> ll(n);
    for (int i = 0; i < n; i++) {
        cin >> ll[i];
        s += ll[i];
    }

    for (int x = 0; x < n; x++) {
        int k = n - x;
        if (s % k != 0) { continue; }
        if (can_reduce_to_zero(ll, k)) {
            cout << k << '\n';
            break;
        }
    }

    return 0;
}