using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;      

public class Program

{

    static Dictionary<char,char> bracketPairs= new Dictionary<char,char>(){{'{','}'},{'[',']'},{'(',')'},{'<','>'}};

​

    public static void Main()

    {

        Console.WriteLine( IsBalanced() ? "YES" : "NO" );

    }

    public static bool IsBalanced(){

            string expression = Console.ReadLine();

            var charArray=expression.ToCharArray();

            var stackBrackets=new Stack<char>(); 

            //Loop through all char in input string and store opening brackets and verify closing brackets.

            foreach(var p in charArray)

            {

                if(bracketPairs.ContainsKey(p))//store opening brackets in stack

                {

                    stackBrackets.Push(p);

                }

                else if(bracketPairs.ContainsValue(p) && stackBrackets.Any()){

                    //this is closing bracket, have a look if previous value was corresponding opening bracket.

                    var openingBracket=stackBrackets.Pop();

                    if(bracketPairs[openingBracket] != p)

                    {

                        //closing bracket not corresponding to opening bracket.

                        return false;

                    }

                }

                else{

                    return false;

                }

            }

            return !stackBrackets.Any(); 

​

    }

}