using System;
using System.Collections.Generic;

namespace Balanced_Parenthesis
{
    class BalancedParenthesis
    {
        static void Main(string[] args)
        {
            char[] inputText = Console.ReadLine().ToCharArray();

            Stack<char> brackets = new Stack<char>();
            bool isBalanced = true;

            foreach (char item in inputText)
            {
                bool isOpenBracket = ((item.Equals('{')) || (item.Equals('[')) || (item.Equals('(')));
                bool isCloseBracket = ((item.Equals('}')) || (item.Equals(']')) || (item.Equals(')')));

                if (isBalanced)
                {
                    if (isOpenBracket)
                    {
                        brackets.Push(item);
                    }
                    else if ((isCloseBracket) && brackets.Count > 0)
                    {
                        if (((int)item == (int)(brackets.Peek() + 1)) || ((int)item == ((int)(brackets.Peek() + 2))))
                        {
                            brackets.Pop();
                        }
                        else
                        {
                            isBalanced = false;
                        }
                    }
                    else
                    {
                        isBalanced = false;
                    }
                }
            }

            if ((isBalanced) && brackets.Count.Equals(0))
            {
                Console.WriteLine("YES");
            }
            else
            {
                Console.WriteLine("NO");
            }
        }
    }
}