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: Wrong Answer)

<?php

$data = $argv[1];
$l = strlen($data);

for($i = 0; $i < $l; $i++) {
	$char = substr($data, $i, 1);
	if (substr_count($data, $char) % 2 == 0 ){
		$result = "YES";
	}
	else{
		$result = "NO";
	}
}

echo $result . "\n";
?>