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

signed main()
{
	int n;
	cin>>n;
	vector<int> a(n);

	for(int i = 0 ; i < n ; i++) 
		cin>>a[i];
	sort(a.begin(),a.end());
	int mn = a[0];

	while(mn>=1){
		int flag = 1;
	for(int i = 1; i < n ; i++)
	{
		if(mn<=a[i]/2)
			break;
		if(a[i] != mn && a[i]%mn != 0){
			flag=0;
			break;
		}
	}
	if(flag){
		cout<<mn<<endl;
		break;
	}
	mn/=2;
}
cout<<max(mn,1ll)<<endl;
	
	
}