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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <algorithm>
#include <deque>
#include <fstream>
#include <iomanip>
#include <iostream>
#include <map> //pair is also included in this library
#include <stack>
#include <string>
#include <vector>

#define INF INT_MAX/3

#define REP(i, s, n) for(int i = (int)(s); i < (int)(n); i++)

using namespace std;

typedef long long int ll;
typedef vector<int> VI;
typedef vector<ll> VL;
typedef pair<int, int> PII;

bool solve(string w){
  sort(w.begin(), w.end());

  char head = w[0];
  ll count = 0;
  bool ans = true;

  if(w.size() % 2 == 0){
    REP(i, 0, w.size()){
      if(head != w[i]){
        if((count % 2) != 0){
          ans = false;
          break;
        }
        count = 1;
        head = w[i];
      }
      count++;
    }
  } else {
    ans = false;
  }
  
  return ans;
}

int main(){
  string w;

  cin >> w;

  if(solve(w)){
    cout << "Yes" << endl;
  } else {
    cout << "No" << endl;
  }
  return 0;
}