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: Accepted)

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

namespace AtCorder
{
    public static class Program
    {
        static public void Main(string[] args)
        {
            //int cnt = int.Parse(Console.ReadLine());
            //double[] input=  Console.ReadLine().Split(' ').Select(double.Parse).ToArray();
            string input = Console.ReadLine();
            char[] cArray = input.ToArray();
            string ans = "";

            if (cArray[2] == cArray[3] && cArray[4] == cArray[5])
            {
                ans = "Yes";
            }
            else
            {
                ans = "No";
            }

            Console.WriteLine(ans);
                        
        }
    }
}