#include<bits/stdc++.h>
using namespace std;
int main()
{
	stack<char>aaa;
	string bbb;
	cin>>bbb;
	int i=0;
	while(bbb[i]!='@')
	{
		if(bbb[i]=')'&&aaa.size()==0){
			cout<<"NO";
			return 0;}
		if(bbb[i]='(')
			aaa.push(bbb[i]);
		if(bbb[i]=')'&&aaa.size()!=0)
			aaa.pop();
		i++;
	}
	if(aaa.size()==0)
		cout<<"YES"	;
	else
		cout<<"NO";
	return 0;
	
}