Program Kruscal;
 type tip=record
       x,y,t:longint;
       end;
var a:array [1..400000] of tip;
    l,sol1,sol2:array [1..100000] of longint;
    i,j,n,m,ct,k,v,w:longint;
    fi,fo:text;
procedure sort(l,r:longint);
 var k,i,j:longint;
    y:tip;
 begin
  i:=l; j:=r;
   k:=a[(l+r) div 2].t;
 repeat
  while a[i].t<k do inc(I);
   while a[j].t>k do dec(j);
 if i<=j then
              begin
               y:=a[i];
                a[i]:=a[j];
                  a[j]:=y;
                     inc(i); dec(j);
              end;
 until i>=j;
  if l<j then sort(l,j);
   if i<r then sort(i,r);
 end;
begin
 assign(fi,'apm.in');
  assign(fo,'apm.out');
 reset(fi); rewrite(fo);
 readln(fi,n,m);
 for i:=1 to n do l[i]:=i;
  for i:=1 to m do readln(fi,a[i].x,a[i].y,a[i].t);
 sort(1,m); i:=1;
   while k<n-1 do begin
     if l[a[i].x]<>l[a[i].y] then begin
                                   inc(k);
                                    ct:=ct+a[i].t;
                                   sol1[k]:=a[i].x; sol2[k]:=a[i].y;
                                    v:=l[a[i].y]; w:=l[a[i].x];
                                   for j:=1 to n do
                                    if l[j]=v then l[j]:=w;
                                   end;
                     inc(i);
     end;
 writeln(fo,ct); writeln(fo,n-1);
 for i:=1 to n-1 do writeln(fo,sol2[i],' ',sol1[i]);
 close(fo);
end.