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#include <bits/stdc++.h>
#define int ll
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define rng(i,c,n) for(int i=c;i<n;i++)
#define fi first
#define se second
#define vec vector
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(),a.end()
typedef long long ll;
typedef vector<int> vi;
typedef pair<int,int> pii;
void print(){cout<<'\n';}
template<class h,class...t>
void print(const h&v,const t&...u){cout<<v<<' ',print(u...);}

void slv(){
	int n;
	cin>>n;

	vi a(n);
	rep(i,n){
		cin>>a[i];
	}

	vi d;
	rep(i,n){
		d.pb(a[i]-(!i?0:a[i-1]));
	}
	d.pb(-a.back());
	n=sz(d);

	int frst=n;
	rep(i,n){
		if(d[i]<0){
			frst=i;
			break;
		}
	}
	// print(frst,n);

	int ans=1;
	for(int k=n-1;k>=2;k--){
		if(k-1>=frst){
			continue;
		}
		bool fnd=0;
		for(int r=0;r<k;r++){
			int now=0;
			for(int i=r;i<n;i+=k){
				now+=d[i];
				if(now<0){
					fnd=1;
					break;
				}
			}
			// print(now,r);
			if(now!=0){
				fnd=1;
				break;
			}
		}
		if(!fnd){
			ans=k;
			break;
		}
	}
	cout<<ans<<"\n";
}

signed main(){
	ios::sync_with_stdio(0),cin.tie(0);

	int t;
	t=1;
	// cin>>t;

	rep(cs,t){
		slv();
	}
}