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
/*
    Problem URL : http://agc004.contest.atcoder.jp/tasks/agc004_b
12-
    Score  :
    Result :
    Time   : ms
    Memory : KB
 */

ini_set('error_reporting', E_ALL & ~E_NOTICE);

fscanf(STDIN, "%s", $w);

$arr = array();
$str = str_split($w);
$len = count($str);

for ($i = 0; $i < $len; $i++) {
    $arr[$str[$i]]++;
}

foreach ($arr as $key => $val) {
    if ($val % 2 !== 0) {
        echo "No\n";
        exit;
    }
}
echo "Yes\n";