#include<iostream>
#include<string>
using namespace std;

int main()
{
	int cnt[26]={};
	string str;
	cin>>str;
	for(int i=0;i<str.length();i++)cnt[str[i]-'a']++;
	bool checker=true;
	for(int i=0;i<26;i++){
		if(cnt[i]%2 != 0){
			checker = false;
			break;
		}
	}
	if(checker)cout<<"YES"<<endl;
	else cout<<"NO"<<endl;
	return 0;
}