var n,m,i,j,k,cnt,lift,sum:longint;
    a:array[0..200001] of longint;
   used:array[0..200001] of boolean;
   och:array[0..200001] of longint;
procedure swap(Var t,y:longint);
var u:longint;
begin
u:=t; t:=y; y:=u;
end;

procedure sort(l,r:longint);
var i,j,x:longint;
begin
 x:=a[random(r-l)+l];
 i:=l; j:=r;
 repeat
 while a[i]<X do inc(i);
 while a[j]>x do dec(j);
 if i<=j then
 begin
  swap(A[i],a[j]);
  inc(i);
  dec(j);
 end;
until i>j;
if l<j then sort(l,j);
if i<r then sort(i,r);
end;




begin
 randomize;
 readln(n,m);
 for i:= 1 to n do
 read(A[i]);
 sort(1,n);
 i:=1;
 j:=n;
 cnt:=0;
 fillchar(used,sizeof(used),true);
 while (i<j) do
  begin
   if a[i]+a[j]<=m then i:=i+1 else
   begin
    inc(cnt);
    och[cnt]:=a[i];
    inc(cnt);
    och[cnt]:=a[j];
    used[i]:=false;
    used[j]:=false;
    i:=i+1;
    j:=j-1;
  end;
 end;
 for i:= n downto 1 do
  if used[i] then
    begin
       inc(cnt);
       och[cnt]:=a[i];
    end;
 lift:=0;
 sum:=0;
 cnt:=0;
 for i:= 1 to n do
 begin
  if (sum+och[i]>m) or (Cnt=2) then
    begin
     lift:=lift+1;
     sum:=och[i];
     cnt:=1;
    end else
  begin
  sum:=sum+och[i];
  cnt:=cnt+1;
  end;
 end;
 if sum>0 then lift:=lift+1;
 writeln(lift);
 for i:= 1 to n do
 write(och[i],' ');
 writeln;
end.