Problem:
Score : 200 points

Problem Statement

There are N children, numbered 1, 2, ..., N.

Snuke has decided to distribute x sweets among them.
He needs to give out all the x sweets, but some of the children may get zero sweets.

For each i (1 \leq i \leq N), Child i will be happy if he/she gets exactly a_i sweets.
Snuke is trying to maximize the number of happy children by optimally distributing the sweets.
Find the maximum possible number of happy children.

Constraints

All values in input are integers.

2 \leq N \leq 100

1 \leq x \leq 10^9

1 \leq a_i \leq 10^9

Input

Input is given from Standard Input in the following format:

N x
a_1 a_2 ... a_N

Output

Print the maximum possible number of happy children.

Sample Input 1

3 70
20 30 10

Sample Output 1

2

One optimal way to distribute sweets is (20, 30, 20).

Sample Input 2

3 10
20 30 10

Sample Output 2

1

The optimal way to distribute sweets is (0, 0, 10).

Sample Input 3

4 1111
1 10 100 1000

Sample Output 3

4

The optimal way to distribute sweets is (1, 10, 100, 1000).

Sample Input 4

2 10
20 20

Sample Output 4

0

No children will be happy, no matter how the sweets are distributed.

Solution in Common Lisp (SBCL 1.1.14) (judge verdict: Wrong Answer)

#-swank
(unless (member :child-sbcl *features*)
  (quit
   :unix-status
   (process-exit-code
    (run-program *runtime-pathname*
                 `("--control-stack-size" "128MB"
                   "--noinform" "--disable-ldb" "--lose-on-corruption" "--end-runtime-options"
                   "--eval" "(push :child-sbcl *features*)"
                   "--script" ,(namestring *load-pathname*))
                 :output t :error t :input t))))
(defmacro dp (name args memo-size &body body)
  (let ((memo (gensym)))
    `(let ((,memo (make-array ,memo-size :initial-element nil)))
       (defun ,name ,args
         (or (aref ,memo ,@args)
             (setf (aref ,memo ,@args)
                   ,@body))))))

(defun split (x str)
  (let ((pos (search x str))
        (size (length x)))
    (if pos
        (cons (subseq str 0 pos)
              (split x (subseq str (+ pos size))))
        (list str))))

(defmacro collect-times (time body)
  `(loop repeat ,time collect ,body))

(defun read-times (time)
  (collect-times time (read)))

(defmacro aif (expr then else)
  `(let ((it ,expr))
     (if it ,then ,else)))

(defmacro awhen (expr &rest then)
  `(aif ,expr (progn ,@then) nil))

(defun comulative (function list &key base)
  (if base
      (comulative function (cons base list))
      (do ((lst (cdr list) (cdr lst))
           (acc (list (car list))))
          ((null lst) (reverse acc))
        (push (funcall function (car acc) (car lst)) acc))))

(defun binary-search (function left right
                      &optional
                        (eps 1)
                        (average-function (lambda (x y) (ash (+ x y) -1))))
  (if (<= (abs (- left right)) eps)
      right
      (let ((mid (funcall average-function left right)))
        (if (funcall function mid)
            (binary-search function left mid eps average-function)
            (binary-search function mid right eps average-function)))))

(defun arithmetic-mean (&rest body)
  (/ (apply #'+ body) (length body)))

(defvar +MOD+ (+ (expt 10 9) 7))

(defun main (n sum kids)
  (let ((sums (coerce (comulative #'+ (sort kids #'<)) 'vector)))
    (- (binary-search (lambda (x) (> (aref sums x) sum)) -1 n)
       (if (< (apply #'+ kids) sum) 1 0))))

(let ((n (read))
      (x (read)))
  (princ (main n x (read-times n))))