var
  a,b,f:array[1..5000] of longint;
  l,r,i,t,te,n,len:longint;
procedure swap(var x,y:longint);
begin if x<>y then begin x:=x xor y;y:=y xor x;x:=x xor y; end; end;
procedure qsort(l,r:longint);
var
  i,j,x,y:longint;
begin
  i:=l;j:=r;x:=b[(l+r) shr 1];y:=a[(l+r) shr 1];
  while i<=j do
    begin
      while (b[i]<x) or ((b[i]=x) and (a[i]<y)) do inc(i);
      while (b[j]>x) or ((b[j]=x) and (a[j]>y)) do dec(j);
      if i<=j then
        begin
          swap(a[i],a[j]);swap(b[i],b[j]);
          inc(i);dec(j);
        end;
    end;
  if l<j then qsort(l,j);
  if i<r then qsort(i,r);
end;
begin
  readln(te);
  for t:=1 to te do
    begin
      readln(n);
      for i:=1 to n do read(a[i],b[i]);
      qsort(1,n);
      f[1]:=a[1];len:=1;
      for i:=2 to n do
        begin
          l:=1;r:=len+1;
          while l< r do
            if a[i]>=f[(l+r) shr 1] then r:=(l+r) shr 1
            else l:=(l+r) shr 1+1;
          f[r]:=a[i];if r>len then len:=r;
        end;
      writeln(len);
    end;
end.