var i,j,n,k,s,aux:longint;
    ok:boolean;
    a:array[1..100000]of longint;
    f,g:text;
begin
 assign(f,'economie.in');
 reset(f);
 readln(f,n);
 for i:=1 to n do
  readln(f,a[i]);
 close(f);
 repeat
  ok:=true;
  for i:=1 to n-1 do
   if a[i]>a[i+1] then begin
    ok:=false;
    aux:=a[i];
    a[i]:=a[i+1];
    a[i+1]:=aux;
    end;
  until ok=true;
  s:=0;
  for i:=1 to n-1 do begin
   s:=s+a[i];
   ok:=true;
   for j:=i+1 to n do
    if a[j] mod s<>0 then ok:=false;
    if ok=true then k:=i;
   end;
 assign(g,'economie.out');
 rewrite(g);
 writeln(g,k);
 for i:=1 to k do
  writeln(g,a[i]);
 close(g);
end.