program ctc;
const fi='ctc.in';
      fo='ctc.out';
var f:text;
g:text;
    var a,tr:array of array of longint;
       v:array of 0..1;
       viz:array[1..100000] of longint;
       bufin,bufout:array[1..70000] of byte;
       n,m,i,c,d,nr:longint;
       s:ansistring;
       s1:string;
procedure df(nod:longint);
var j:longint;
begin
v[nod]:=1;
for j:=1 to a[nod,0] do
   if v[a[nod,j]]=0 then
      df(a[nod,j]);
end;
procedure trs(nod:longint);
var j:longint;
begin
if v[nod]=1 then
begin
str(nod,s1);
s:=s+s1+' ';

viz[nod]:=1;
end;
for j:=1 to tr[nod,0] do
   if viz[tr[nod,j]]=0 then
      trs(tr[nod,j]);
end;
begin
assign(f,fi);
reset(f);
assign(g,fo);
rewrite(g);
settextbuf(f,bufin);
settextbuf(g,bufout);
read(f,n,m);
for i:=1 to m do
  begin
  read(f,c,d);
  inc(a[c,0]);
  setlength(a[c],a[c,0]+1);
  a[c,a[c,0]]:=d;
  inc(tr[d,0]);
  setlength(tr[d],tr[d,0]+1);
  tr[d,tr[d,0]]:=c;
  end;
for i:=1 to n do
  begin
  if viz[i]=0 then
  begin
  setlength(v,0);
  setlength(v,n+1);
  df(i);
  trs(i);
  inc(nr);
  s:=s+#13#10
  end;
  end;
  str(nr,s1);
  s1:=s1+#13#10;
  insert(s1,s,1);
  write(g,s);

  close(f);
  close(g);
  end.