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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;

namespace AtCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            //[summary]B - 美しい文字列 / Beautiful Strings
            var w = Console.ReadLine();
            var chars = new Dictionary<char, int>();

            foreach(var c in w)
            {
                if (!chars.ContainsKey(c))
                {
                    chars.Add(c, 1);
                }
                else
                {
                    chars[c]++;
                }
            }

            if (IsBeautifulStrings(chars))
            {
                Console.WriteLine("Yes");
            }
            else
            {
                Console.WriteLine("No");
            }
        }

        static bool IsBeautifulStrings(Dictionary<char, int> chars)
        {
            foreach(var v in chars.Values)
            {
                if (v % 2 != 0)
                {
                    return false;
                }
            }

            return true;
        }
    }
}