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.IO;
using System.Linq;

    class Program
    {
        static void Main(string[] args)
        {
            var KN = Console.ReadLine().Split(' ');

            var K = int.Parse(KN[0]);
            var N = int.Parse(KN[1]);

            var distances = Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToArray();
            var longdisIndex = 0;
            var longdis = 0;
            for(int i =0; i < N;i++)
            {
                var dis =  distances[i] - distances[(i + 1) % N];
                if(dis > longdis)
                {
                    longdisIndex = i;
                }
            }

            var before = longdisIndex - 1;
            if(before < 0)
            {
                before += K;
            }

            var ret = K - distances[longdisIndex] + distances[before];
            
            MyConsoleWrightLine(ret.ToString());
        }

        private static void MyConsoleWrightLine(string str)
        {
            var sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
            Console.SetOut(sw);

            Console.WriteLine(str);

            Console.Out.Flush();
        }
}