#include<iostream>
#include<stack>
using namespace std;
int main()
{
char a[300];
int i=0;
stack<char>m;
cin>>a;
while(a[i]!='@')
{
if(a[i]=='(')
m.push(a[i]);
else if(a[i]==')'&&m.empty()==0)
m.pop();
else if(a[i]==')'&&m.empty()!=0)
{
cout<<"NO";
return 0;
}
i++; ///加上不然死循环了;
}
if(m.empty()==0)
cout<<"NO";
else
cout<<"YES";
return 0;
}
#include<stack>
using namespace std;
int main()
{
char a[300];
int i=0;
stack<char>m;
cin>>a;
while(a[i]!='@')
{
if(a[i]=='(')
m.push(a[i]);
else if(a[i]==')'&&m.empty()==0)
m.pop();
else if(a[i]==')'&&m.empty()!=0)
{
cout<<"NO";
return 0;
}
i++; ///加上不然死循环了;
}
if(m.empty()==0)
cout<<"NO";
else
cout<<"YES";
return 0;
}