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

const int MAX_N=100005;

int a[MAX_N];
long long x[MAX_N];

bool check(int k, int n, long long s)
{
    if(s%k!=0)
    {
        return false;
    }

    for(int i=1; i<=n; i++)
    {
        long long diff=(long long)a[i]-a[i-1];

        x[i]=diff+(i>k ? x[i-k] : 0);

        if(x[i]<0)
        {
            return false;
        }

        if(i>n-k+1 && x[i]!=0)
        {
            return false;
        }
    }

    return true;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin>>n;

    long long total=0;

    a[0]=0;

    for(int i=1; i<=n; i++)
    {
        cin>>a[i];

        total+=a[i];
    }

    int l=1;
    int r=1;

    while(l<n && a[l+1]>=a[l])
    {
        l++;
    }

    while(r<n && a[n-r]>=a[n-r+1])
    {
        r++;
    }

    int possible=min({n,l,r});

    vector<int> candidates;

    for(long long d=1; d*d<=total; d++)
    {
        if(total%d==0)
        {
            if(d<=(long long)possible)
            {
                candidates.push_back((int)d);
            }

            if(total/d<=(long long)possible)
            {
                candidates.push_back((int)(total/d));
            }
        }
    }

    sort(candidates.rbegin(),candidates.rend());

    candidates.erase(unique(candidates.begin(),candidates.end()),candidates.end());

    for(int k : candidates)
    {
        if(check(k,n,total))
        {
            cout<<k<<endl;
            return 0;
        }
    }

    cout<<1<<endl;

    return 0;
}