program firework;
var
  cost:array[0..1000,0..1000] of integer;
  q,fa,dist,fa2,path:array[0..1000] of integer;
  bb:array[0..1000] of boolean;
  b:array[0..1000,0..1000] of boolean;
  tt,n,k,i,j,s,max,maxs,maxi,max2,max2s,max2i,p,tot,r1,r2,t,h:integer;
begin
  assign(input,'firework.in');
  reset(input);
  assign(output,'firework.out');
  rewrite(output);
  readln(tt);
  for k:=1 to tt do
  begin
    readln(n);
    fillchar(cost,sizeof(cost),0);
    fillchar(fa2,sizeof(fa2),0);
    for i:=1 to n-1 do
    begin
      readln(r1,r2);
      cost[r1,r2]:=-1;
      cost[r2,r1]:=-1;
    end;
    max2:=0;
    for s:=1 to n do
    begin
      fillchar(bb,sizeof(bb),false);
      fillchar(dist,sizeof(dist),0);
      fillchar(q,sizeof(q),0);
      fillchar(fa,sizeof(fa),0);
      fillchar(b,sizeof(b),false);
      h:=0;
      t:=1;
      q[t]:=s;
      bb[s]:=true;
      b[s,s]:=true;
      while h<>t do
      begin
        h:=(h mod n)+1;
        for i:=1 to n do
        begin
          if (cost[q[h],i]<0) and (dist[q[h]]+cost[q[h],i]<dist[i]) and (b[q[h],i]=false) then
          begin
            dist[i]:=dist[q[h]]+cost[q[h],i];
            fa[i]:=q[h];
            b[i]:=b[q[h]];
            b[i,i]:=true;
            if bb[i]=false then
            begin
              t:=(t mod n)+1;
              q[h]:=i;
              bb[i]:=true
            end
          end
        end;
        bb[q[h]]:=false;
      end;
      max:=0;
      for i:=1 to n do
        if dist[i]<max then
        begin
          max:=dist[i];
          maxs:=s;
          maxi:=i;
        end;
      if max<max2 then
      begin
        max2:=max;
        max2s:=maxs;
        max2i:=maxi;
        fa2:=fa
      end
    end;
    writeln(-max2);
    p:=max2i;
    tot:=0;
    repeat
      tot:=tot+1;
      path[tot]:=p;
      p:=fa2[p];
    until p=max2s;
    writeln(max2s);
    for i:=tot downto 1 do
      writeln(path[i]);
  end;
  close(input);
  close(output)
end.