#-swank
(unless (member :child-sbcl *features*)
  (quit
   :recklessly-p t
   :unix-status
   (process-exit-code
    (run-program *runtime-pathname*
                 `("--control-stack-size" "1024MB"
                   "--noinform" "--disable-ldb" "--lose-on-corruption" "--end-runtime-options"
                   "--eval" "(push :child-sbcl *features*)"
                   "--script" ,(namestring *load-pathname*))
                 :output t :error t :input t))))

(defun read-integers ()
  (with-open-file (stream *standard-input* :direction :input :external-format :utf-8)
    (loop for line = (read-line stream nil)
          while line
          append (mapcar #'parse-integer (split-sequence-from-string line)))))

(defun split-sequence-from-string (str)
  (let ((start 0)
        (len (length str))
        (result '()))
    (loop for i from 0 to len
          when (or (eql i len) (char= (char str i) #\Space))
          do (when (> i start)
               (push (parse-integer (subseq str start i)) result))
             (setf start (1+ i)))
    (nreverse result)))

(defun union-find-make (n)
  (let ((parent (make-array n :initial-contents (loop for i from 0 below n collect i)))
        (rank (make-array n :initial-element 0)))
    (values parent rank)))

(defun union-find-find (parent x)
  (if (/= (aref parent x) x)
      (setf (aref parent x) (union-find-find parent (aref parent x))))
  (aref parent x))

(defun union-find-union (parent rank x y)
  (let ((root-x (union-find-find parent x))
        (root-y (union-find-find parent y)))
    (unless (= root-x root-y)
      (cond ((> (aref rank root-x) (aref rank root-y))
             (setf (aref parent root-y) root-x))
            ((< (aref rank root-x) (aref rank root-y))
             (setf (aref parent root-x) root-y))
            (t
             (setf (aref parent root-y) root-x)
             (incf (aref rank root-x)))))))

(defun main ()
  (let* ((data (read-integers))
         (N (first data))
         (S (second data))
         (P (subseq data 2 (+ 2 N)))
         (indexed-P (loop for i from 0 below N collect (cons (nth i P) i)))
         (sorted-P (sort (copy-list indexed-P) #'< :key #'car))
         (parent-rank (multiple-value-list (union-find-make N)))
         (parent (nth 0 parent-rank))
         (rank (nth 1 parent-rank))
         (result '()))
    (loop for i from 0 below (1- N)
          for (val1 . idx1) = (nth i sorted-P)
          for (val2 . idx2) = (nth (1+ i) sorted-P)
          when (<= (- val2 val1) S)
          do (union-find-union parent rank idx1 idx2))
    (loop for i from 0 below N
          for root = (union-find-find parent i)
          if (= root i)
          do (push (1+ i) result))
    (setf result (sort result #'<))
    (with-open-file (stream *standard-output* :direction :output :external-format :utf-8)
      (format stream "~d~%" (length result))
      (dolist (elem result)
        (format stream "~d " elem))
      (terpri stream))))

(main)