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#include<bits/stdc++.h>
using namespace std;
using ll=long long;

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin>>n;
    vector<int>a(n),v;
    ll s=0;
    for(int i=0;i<n;++i)cin>>a[i],s+=a[i];
    for(ll i=1;i*i<=s;++i)if(s%i==0){
        if(i<=n)v.push_back(i);
        if(i*i!=s&&s/i<=n)v.push_back(s/i);
    }
    sort(v.rbegin(),v.rend());
    vector<ll>d(n+1);
    auto ok=[&](int k){
        fill(d.begin(),d.end(),0);
        ll c=0;
        for(int i=0;i<n;++i){
            c+=d[i];
            if(i<=n-k){
                if(c>a[i])return 0;
                ll x=a[i]-c;
                c+=x;
                d[i+k]-=x;
            }else if(c!=a[i])return 0;
        }
        return 1;
    };
    for(int k:v)if(ok(k))return cout<<k<<'\n',0;
}