{type vevtor=array[1..1000] of 1..50000;
     vector2=array[1..50000] of 0..1;
                                      }
var
    v,sol:array[1..1000] of 1..50000;
    v2:array[1..50000] of 0..1;
   y, i,j,x,k,kkt,aux,s,n,w,ww,www:longint;
    f,g:text;
    ok:boolean;

begin
assign(f,'economie.in'); assign(g,'economie.out');
reset(f); rewrite(g);
readln(f,n);
for y:=1 to 50000 do v2[y]:=0;
for i:=1 to n do
 begin
readln(f,v[i]);
 end;
ok:=true;
while ok do
begin
ok:=false;
for i:=1 to n-1 do


 if  v[i]>v[i+1] then begin ok:=true; aux:=v[i]; v[i]:=v[i+1]; v[i+1]:=aux;end;

end;
kkt:=v[n];   s:=1; sol[1]:=v[1]; s:=2; x:=v[1];
w:=kkt div v[1];
for j:=x to w do
  v2[j*v[1]]:=1;
for i:=2 to n do

 if v2[v[i]]=0 then
      begin
      sol[s]:=v[i];
      inc(s);
      ww:=kkt div v[i];
      for j:=x to ww  do
       begin
       v2[j*v[i]]:=1;
       www:=kkt-(v[i]+x);
       for k:=x to www do
        if v2[k]<>0 then
         v2[v[i]+k]:=1;
       end;
      end;

writeln(g,s-1);
for i:=1 to s-1 do
 writeln(g,sol[i]);

 close(f); close(g);

end.