program bly(input,ouput);
type
  t1=array[1..100] of integer;
var
  f1,f2:text;
  g:t1;
  i,j,left,right:integer;
  n,s,ans,m:integer;

  procedure QuickSort(var A: t1;Hi: Integer);

    procedure Sort(l, r: Integer);
    var
      i, j, x, y: integer;
    begin
    i := l; j := r; x := a[(l+r) DIV 2];
    repeat
      while a[i] < x do i := i + 1;
      while x < a[j] do j := j - 1;
      if i <= j then
      begin
        y := a[i]; a[i] := a[j]; a[j] := y;
        i := i + 1; j := j - 1;
      end;
    until i > j;
    if l < j then Sort(l, j);
    if i < r then Sort(i, r);
  end;
  begin {QuickSort};
  Sort(1,Hi);
  end;
begin
  assign(f1,'group.in');
  reset(f1);
  readln(f1,s);
  readln(f1,n);
  for i:=1 to n do readln(f1,g[i]);
  close(f1);

  quicksort(g,n);
  left:=1; right:=n; m:=0;
  repeat
    if g[left]+g[right]>s then begin
      dec(right); inc(ans); m:=m+1;
    end;
    if g[left]+g[right]<=s then begin
      inc(left); dec(right); inc(ans); m:=m+2;
    end;
  until left=right;
  assign(f2,'group.out');
  rewrite(f2);
  if m+1=n then writeln(f2,ans+1)
           else writeln(f2,ans);
  close(f2);
end.