(define (iota n . args)
  (let ((start (if (pair? args) (car args) 0))
        (step  (if (and (pair? args) (pair? (cdr args))) (cadr args) 1)))
    (let loop ((m n) (last (+ start (* step (- n 1)))) (a '()))
      (if (zero? m)
          a
	  (loop (- m 1) (- last step) (cons last a))))))

(define (take-candy a)
  (let ((a (sort a <)))
    (cons (- (car a) 1) (cdr a))))
    
(define (take-candy-rec M C)
  (let ((C (filter positive? C)))
    (if (zero? M)
	C
        (take-candy-rec (- M 1) (take-candy C)))))

(define (solve N M C)
  (- N (length (take-candy-rec M C))))
		
(display (let* ((N (read)) (M (read)) (C (map (lambda (x) (read)) (iota N)))) (solve N M C)))
(newline)