Problem:
Score : 200 points

Problem Statement

Let w be a string consisting of lowercase letters.
We will call w beautiful if the following condition is satisfied:

Each lowercase letter of the English alphabet occurs even number of times in w.

You are given the string w. Determine if w is beautiful.

Constraints

1 \leq |w| \leq 100

w consists of lowercase letters (a-z).

Input

The input is given from Standard Input in the following format:

w

Output

Print Yes if w is beautiful. Print No otherwise.

Sample Input 1

abaccaba

Sample Output 1

Yes

a occurs four times, b occurs twice, c occurs twice and the other letters occur zero times.

Sample Input 2

hthth

Sample Output 2

No

Solution in Common Lisp (SBCL 1.1.14) (judge verdict: Accepted)

(defun func(x)
  (or (not (car x)) (and (car x) (cdr x) (char= (car x) (cadr x)) (func (cddr x)))))

(let ((x (concatenate 'list (sort (read-line) #'char<))))
  (princ (if (func x)
		   "Yes"
		   "No")))