type
  pointer=^rec;
  rec=record
    k:longint;
    next:pointer;
  end;

var
  cover:array[1..200]of boolean;
  link:array[1..200]of pointer;
  ans,du:array[1..200]of longint;
  n,m,t,k,i:longint;


  procedure init;
  var
    i,a,b:longint;
    p:pointer;
  begin
    readln(n,m);
    for i:=1 to n do link[i]:=nil;
    fillchar(du,sizeof(du),0);
    for i:=1 to m do
      begin
        readln(a,b);
        new(p);
        p^.k:=a;
        p^.next:=link[b];
        link[b]:=p;
        inc(du[a]);
      end;
  end;

  procedure main;
  var
    i:longint;
    bool:boolean;
    p:pointer;
  begin
    k:=0;
    fillchar(cover,sizeof(cover),false);
    while bool do
      begin
        bool:=false;
        for i:=n downto 1 do
          if (du[i]=0)and(not cover[i]) then
            begin
              inc(k);
              ans[i]:=k;
              p:=link[i];
              while p<>nil do
                begin
                  dec(du[p^.k]);
                  p:=p^.next;
                end;
              cover[i]:=true;
              bool:=true;
              break;
            end;
      end;
  end;

  procedure outit;
  var
    i:longint;
  begin
    if k<n then writeln(-1) else
      begin
        for i:=1 to k do
          begin
            if i<>1 then write(' ');
            write(n+1-ans[i]);
          end;
        writeln;
      end;
  end;

begin
  readln(t);
  for i:=1 to t do
    begin
      init;
      main;
      outit;
    end;
end.