#include <fstream.h>
int main ()
{ long v[1000],n,i,j,s,x,p,aux,k2;
int ok;
ifstream f ("economie.in");
ofstream g ("economie.out");
f>>n;
for (i=1; i<=n; i++) {
    f>>v[i]; }
do { ok=1;
     for (i=1;i<=n-1;i++){
	    if (v[i]>v[i+1]) {
		    aux=v[i];
		    v[i]=v[i+1];
		    v[i+1]=aux;
		    ok=0; }}
    } while (ok==0);
ok=0; s=0; i=1;
 while (ok==0 && i<=n) {
		 s=s+v[i]; j=i+1; k2=0;
		 do { if (v[j]-s==0) {k2++; j++; }
		      else { p=v[j]-s; x=1;
		             while (ok==0 && x<j-k2) {
	                          if (p%v[x]==0) ok=1;
	                          else x++;      } }
		     } while (ok==0 && j!=i+1);
		 i=i+1; }
 g<<i-1<<endl;
for (j=1;j<=i-1;j++){
	  g<<v[j]<<endl; }
f.close ();
g.close ();
return 0;
}