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#ifdef DEBUG
#define _GLIBCXX_DEBUG
#endif
//#pragma GCC optimize("O3")
#include<bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#else
#define debug(...) 228
#endif


typedef long long ll;
typedef long double ld;

#define pb push_back
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) FOR(i, 0, a)

vector<int> read_vec(int n) {
    vector<int> v(n);
    for (int& t : v) cin >> t;
    return v;
}

template<typename T>
inline void upd_max(T& a, T b) {
    if (a < b) {
        a = b;
    }
}

template<typename T>
inline void upd_min(T& a, T b) {
    if (a > b) {
        a = b;
    }
}

const int maxN = 1e5 + 10;
int n;
int a[maxN];
int p[maxN];
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
#ifdef DEBUG
    freopen("input.txt", "r", stdin);
#endif
    cin >> n;
    ll S = 0;
    FOR(i, 1, n + 1) {
        cin >> a[i];
        S += a[i];
    }
    auto test = [&](int k) {
        int sum = 0;
        memset(p, 0, sizeof p);
        FOR(i, 1, n + 1) {
            if (i - k >= 1) sum -= p[i - k];
            if (sum > a[i]) return false;
            p[i] = a[i] - sum;
            if (i + k - 1 > n && p[i] != 0) return false;
            sum = a[i];
        }
        return true;
    };
    int mx = 0;
    for (int k = n; k >= 1; k--) {
        if (S % k == 0 && test(k)) upd_max(mx, k);
    }
    cout << mx << '\n';
    return 0;
}