#include <iostream>
using namespace std;
int prim(int m)
{
int p=1;
if (m<2) p=0;
else
{
if (m==2) p=1;
if (m>2)
{
if (m%2==0) p=0;
else
{
for (int j=3; j*j<=m; j+=2)
if (m%j==0) { p=0; break;}
}
}
}
return p;
}
int transforma(int v[], int n)
{
int k=-1, prime=0;
for (int i=0; i<n; ++i)
{
if (prim(v[i]))
{
++k; v[k]=v[i]; ++prime;
}
}
return prime;
}
int main()
{
int n, i, v[100];
cin >> n;
for (i=0; i<n; ++i)
cin >> v[i];
cout << transforma(v, n) << "\n";
for (i=0; i<n; ++i)
cout << v[i] << " ";
}