var n, i,dif, nr1: longint;
    a: array [1..65000] of byte;
    f,g: text;
begin
assign (f, 'multimi2.in');
assign (g, 'multimi2.out');
reset (f);
rewrite (g);
readln (f, n);
for i:=1 to n do readln (f, a[i]);
i:=n;
while (i-4)>=0 do begin a[i]:=1;
                        a[i-1]:=2;
                        a[i-2]:=2;
                        a[i-3]:=1;
                        i:=i-4;
                  end;
nr1:= (n div 4)*2;
case i of 0: dif:=0;
          1: begin
             a[1]:=1;
             dif:=1;
             nr1:= nr1+1;
             end;
          2: begin
             a[1]:= 1;
             a[2]:= 2;
             dif :=1;
             nr1:= nr1+1;
             end;
          3: begin
             a[1]:=1;
             a[2]:= 1;
             a[3]:=2;
             dif:=0;
             nr1:= nr1+2;
             end;
          end;
writeln (g, dif);
writeln (g, nr1);
for i:=1 to n do if a[i]= 1 then write (g, i, ' ');
writeln (g);
writeln (g, n-nr1);
for i:=1 to n do if a[i]=2 then write (g, i, ' ');
close (f);
close (g);
end.