#include<bits/stdc++.h>
using namespace std;
int main(){
	int n=0,k=0;
char s;
while(1){
	cin>>s;
	if(s=='@') break;
	if(s=='(') n++;
	if(s==')') k++; 
}
if(n==k) cout<<"YES";
else cout<<"NO";
	return 0;
}