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

using namespace std;

#define int long long

bool czy(int k, const vector<int>& pref, int n){
    vector<int> tab(k, 0);
    for(int i=1; n+1>=i; i++){
        int mod = i % k;
        tab[mod] += pref[i];
        if(i <= n - k + 1){
            if(tab[mod] < 0) return false;
        }else{
            if(tab[mod] != 0) return false;
        }
    }
    return true;
}

signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n; cin>>n;
    vector<int>A(n+1, 0);
    int sum = 0;
    for(int i=1; n>=i; i++){
        cin >> A[i];
        sum += A[i];
    }
    vector<int>pref(n+2, 0);
    for(int i=1; n>=i; i++){
        pref[i] = A[i] - A[i - 1];
    }
    pref[n+1] = -A[n];
    vector<int> divs;
    for(int i=1; sum>=i*i; i++){
        if(sum % i == 0){
            if(i <= n) divs.push_back(i);
            int j = sum / i;
            if(j != i and j <= n) divs.push_back(j);
        }
    }
    sort(divs.rbegin(), divs.rend());
    for(auto x : divs){
        if(czy(x, pref, n)){
            cout<<x;
            return 0;
        }
    }
    cout<<1;
}