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 Ruby (2.3.3) (judge verdict: Wrong Answer)

a = gets.chomp.split("")
b = []
c = 0
d = a.uniq
d.length.times do
  if a.count(d[c]) % 2 == 0
    c += 1
    b.push("YES")
  else
    c += 1
    b.push("NO")
  end
end


if b.include?("NO")
  puts "NO"
else
  puts "YES"
end