#include <iostream>
#include <stack>
#include <string>
using namespace std;

int main(){
	stack<char> c;
	string s;
	cin >> s;
	for(int i = 0;i < s.size();i++)
	{
		if(s[i] == '(' || s[i] == '[' )
		{
			c.push(s[i]);
		}
		else if(s[i] == ']')
		{
			if(!c.empty() && c.top() == '[') c.pop();
			else c.push(s[i]);
		}
		else if(s[i] == ')')
		{
			if(!c.empty() && c.top() == '(') c.pop();
			else c.push(s[i]);
		}
	}
	if(c.empty()) printf("YES");
	else printf("NO");
	return 0;
}

记得在出栈时判断栈是否为空，否则runtime error