var f,g:text;
    n,i,j,ok,l,e,nr,k:longint;
    a,r:array[1..50000]of longint;
begin
assign(f,'secv2.in');reset(f);
assign(g,'secv2.out');rewrite(g);
readln(f,n);
for i:=1 to n do
    readln(f,a[i]);
    r[1]:=a[1] mod 3;
for i:=2 to n do
    begin
    r[i]:=r[i-1]+a[i];
    r[i]:=r[i] mod 3;
    end;
for i:=1 to n-1 do
    begin
         for j:=n downto i+1 do
             if r[i]=r[j] then
                              begin
                              ok:=i;
                              for l:=i+1 to j do
                              nr:=nr+1;
                              break;
                              end;
             k:=i;
             e:=j;
           if ok<>0 then break;
    end;
writeln(g,nr);
for i:=1 to k do
    write(g,a[i],' ');
for i:=e+1 to n do
    write(g,a[i],' ');
close(g);
end.