#include<bits/stdc++.h>
using namespace std; 
int a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s1,t,u,v,w,x,y,z;
int main()
{
	string s;
	cin>>s;
	for(int i=0;i<s.size();i++)
	{
		if(s[i]=='a'){
			a++;
		}
		if(s[i]=='b'){
			b++;
		}
		if(s[i]=='c'){
			c++;
		}
		if(s[i]=='d'){
			d++;

		}
		if(s[i]=='e'){
			e++;

		}
		if(s[i]=='f'){
			f++;

		}
		if(s[i]=='g'){
			g++;

		}
		if(s[i]=='h'){
			h++;

		}
		if(s[i]=='i'){
			i++;

		}
		if(s[i]=='j'){
			j++;

		}
		if(s[i]=='k'){
			k++;

		}
		if(s[i]=='l'){
			l++;

		}
		if(s[i]=='m'){
			m++;

		}
		if(s[i]=='n'){
			n++;

		}
		if(s[i]=='o'){
			o++;

		}
		if(s[i]=='p'){
			p++;

		}
		if(s[i]=='q'){
			q++;

		}
		if(s[i]=='r'){
			r++;

		}
		if(s[i]=='s'){
			s1++;

		}
		if(s[i]=='t'){
			t++;

		}
		if(s[i]=='u'){
			u++;

		}
		if(s[i]=='v'){
			v++;

		}
		if(s[i]=='w'){
			w++;

		}
		if(s[i]=='x'){
			x++;

		}
		if(s[i]=='y'){
			y++;

		}
		if(s[i]=='z'){
			z++;

		}
	}
	if(a%2==0&&b%2==0&&c%2==0&&d%2==0&&e%2==0&&f%2==0&&g%2==0&&h%2==0&&i%2==0&&j%2==0&&k%2==0&&l%2==0&&m%2==0&&n%2==0&&o%2==0&&p%2==0&&q%2==0&&r%2==0&&s1%2==0&&t%2==0&&u%2==0&&v%2==0&&w%2==0&&x%2==0&&y%2==0&&z%2==0)
		cout<<"YES";
	else
		cout<<"NO";
	return 0;
}