#include<bits/stdc++.h>
using namespace std;
string s;
stack<char>st;
int main(){
	cin>>s;
	for(int i=0;i<s.size();i++){
		if(s[i]==')'){
			if(st.empty()||st.top()!='('){
				cout<<"no";
				return 0;
			}
			st.pop();
		}
		else if(s[i]==']'){
			if(st.empty()||st.top()!='['){
				cout<<"no";
				return 0;
			}
			st.pop();		
		}
		else st.push(s[i]);
	}
	if(st.empty()){
		cout<<"yes";
		return 0;
	}
	cout<<"no";
}
/**************************************************************
	Problem: 1486
	User: chenshuo
	Language: C++
	Result: Accepted
	Time:26 ms
	Memory:2080 kb
****************************************************************/