why WA2??
program ural;
var n,a,b,y:byte;
    m,i,z,r:integer;
    h,g:array[1..200]of integer;
    t:array[1..32767]of byte;
    l:array[1..32767]of integer;
    p,q:array[1..32767]of boolean;
    s:array[1..200]of byte;
    k:array[1..400]of integer;
    o:array[1..400]of byte;
    u:array[1..200]of boolean;
    x:boolean;
procedure search(d:byte);
var r:integer;
  begin
    u[d]:=true;
    r:=h[d];
    while r<>0 do
      begin
        if u[t[r]]=false then
          begin
            inc(y);
            k[y]:=g[d];
            g[d]:=y;
            o[y]:=t[r];
            inc(y);
            k[y]:=g[t[r]];
            g[t[r]]:=y;
            o[y]:=d;
            p[r]:=true;
            if q[r] then
              p[r+1]:=true
            else
              p[r-1]:=true;
            search(t[r]);
          end;
        r:=l[r];
      end;
  end;
procedure track(v,d:byte);
var r:byte;
  begin
    if d=i then
      begin
        write(v,' ');
        for r:=1 to v-1 do
          write(s[r],' ');
        writeln(d);
        x:=true;
        exit;
      end;
    u[d]:=true;
    s[v]:=d;
    r:=g[d];
    while r<>0 do
      begin
        if u[o[r]]=false then
          track(v+1,o[r]);
        if x then
          exit;
        r:=k[r];
      end;
  end;
begin
  assign(input,'travel.in');
  assign(output,'travel.out');
  reset(input);
  rewrite(output);
  readln(n,m);
  for i:=1 to m do
    begin
      readln(a,b);
      inc(r);
      l[r]:=h[a];
      h[a]:=r;
      t[r]:=b;
      q[r]:=true;
      inc(r);
      l[r]:=h[b];
      h[b]:=r;
      t[r]:=a;
    end;
  z:=m-n;
  for i:=1 to n do
    if u[i]=false then
      begin
        inc(z);
        search(i);
      end;
  if z<=0 then
    begin
      writeln(0);
      exit;
    end
  else
    writeln(z);
  for i:=1 to n do
    begin
      r:=h[i];
      while r<>0 do
        begin
          if(q[r])and(p[r]=false)then
            begin
              x:=false;
              fillchar(u,sizeof(u),false);
              track(1,t[r]);
            end;
          r:=l[r];
        end;
    end;
end.