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 PHP (5.6.30) (judge verdict: Accepted)

<?php
/*
  http://abc044.contest.atcoder.jp/tasks/abc044_b
*/

function is_even($value) {
  return $value % 2 === 0 ? true : false;
}

$stdin = trim(fgets(STDIN));
$str_hash = [];

foreach (str_split($stdin) as $key => $value) {
  if (isset($str_hash[$value])) {
    $str_hash[$value] += 1;
  } else {
    $str_hash[$value] = 1;
  }
}

$is_beautiful = true;
foreach ($str_hash as $key => $value) {
  if (!is_even($value)) {
    $is_beautiful = false;
    break;
  }
}

echo $is_beautiful ? "Yes" : "No";

?>