#include <iostream>
using namespace std;

int v[100], n;
bool prim (int n)
{
   int i=0;
   for (i=2;i<=n/2;i++)
   if (n%i==0)
   return 1;
   return 0;
}

int cmmdc(int a,int b)
{
if(a==b) return a;
else
if (a>b) return cmmdc(a-b,b);
else return cmmdc(a,b-a);
}


int main ()
{

int n; int cmmd, i;
cin>>n; int ind1,ind2;
for (i=1;i<=n;i++)
cin>>v[i];
for (i=1;i<=n;i++)
if (prim(v[i])==1)
{ind1=i;
break;}
for (i=ind1;i<=n;i++)
if ( prim(v[i])==1)
    {ind2=i;
    break;}
cmmd=cmmdc(v[ind1],v[ind2]);
i++;
while (i<=n)
{   if ( prim(v[i])==1)
    cmmd=cmmdc(cmmd,v[i]);
    i++;
}
cout<<cmmd;

return 0;
}