Problem:
Score : 100 points

Problem Statement

A string of length 6 consisting of lowercase English letters is said to be coffee-like if and only if its 3-rd and 4-th characters are equal and its 5-th and 6-th characters are also equal.

Given a string S, determine whether it is coffee-like.

Constraints

S is a string of length 6 consisting of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S

Output

If S is coffee-like, print Yes; otherwise, print No.

Sample Input 1

sippuu

Sample Output 1

Yes

In sippuu, the 3-rd and 4-th characters are equal, and the 5-th and 6-th characters are also equal.

Sample Input 2

iphone

Sample Output 2

No

Sample Input 3

coffee

Sample Output 3

Yes

Solution in C# (Mono 4.6.2.0) (judge verdict: Runtime Error)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            var line = Console.ReadLine();
            if (CheckSimCoffee(line))
            {
                Console.WriteLine("Yes");
            }
            else
            {
                Console.WriteLine("No");
            }

            //Console.WriteLine("hello world");
            //while (true)
            //{
            //    var line= Console.ReadLine();
            //    Console.WriteLine(line);
            //}
        }

        private static bool CheckSimCoffee(string line)
        {
            if (line.Length != 6) return false;
            return line[3] == line[4] && line[5] == line[6];
        }
    }
}