program preONI2008;
var f,g:Text;
		n,i,j,poz,k:integer;
		v:array[1..100] of longint;
		m,min,pb,aux,s:longint;
		ok:boolean;

begin
assign (f,'economie.in'); reset(f);
assign (g,'economie.out'); rewrite(g);
read(f,n);
for i:=1 to n do readln(f,v[i]);

{sortare prin metoda minimului}
for i:=1 to n-1 do
	begin
	min:=v[i];
	poz:=i;
	for j:=i+1 to n do if v[j]<min then begin
																			min:=v[j];
																			poz:=j;
																			end;
	aux:=v[poz];
	v[poz]:=v[i];
	v[i]:=aux;
	end;
{sfarsit sortare}
k:=1;
for i:=2 to n do
	begin
	s:=v[i];
	for j:=i-1downto k do begin
													while (s>=0)  do s:=s-v[j];
													s:=s+v[j];
													end;
	if(i=j+1) then s:=0;
	if s<>0 then k:=k+1;
	end;
writeln(g,k);
for j:=k to i-2 do writeln(g,v[j]);

close(f);
close(g);
end.