#include<iostream>
#include<bits/stdc++.h>
#include<cstring>
#include<stack>
using namespace std;
int main(){
	string a;
	cin>>a;
	stack<int> s;
	for(int i=0;i<a.size();i++)
	{
	   if(a[i]=='@'){
	 	break;
	 }
	    if(a[i]=='('){
     	s.push(a[i]);
		} 	
	    else if(a[i]==')')
		{
			if(s.size())
			s.pop();

		else{
			cout<<"NO";
			return 0;
		}
	 }
	 
	} 
	
		if(s.size()){
			cout<<"No"<<endl;
		}else{
			cout<<"YES"<<endl;
		}
}