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: Wrong Answer)

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Diagnostics;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using System.Numerics;
using System.IO;
using System.Runtime.InteropServices;
using static System.Math;
using static Math2;
using static io;
using static Utils;

public class ACCEPTED
{
    public void Solve()
    {

    }
}

public static class Graph
{

}



public static class Math2
{
    const int INF = 1 << 29;
    const long INFL = 1L << 60;
    const int MOD = 1000000007;
    const int MOD2 = 998244353;

    public static long Pow(long i, long N, long MOD = 1000000007)
    {
        long res = 1;
        while (N > 0)
        {
            if ((N & 1) != 0) res = res * i % MOD;
            i = i * i % MOD;
            N >>= 1;
        }
        return res;
    }
    public static long GCD(long i, long N)
    {
        while (N != 0)
        {
            var r = i % N;
            i = N;
            N = r;
        }
        return i;
    }
    public static long LCM(long i, long N) => i * N / GCD(i, N);
    public static long Comb(long N, long R, int MOD = 1000000007)
    {
        long ret = 1;
        long x = 1;
        for (long i = N; i >= N - R + 1; --i)
        {
            ret = ret / x * i;
            ret %= MOD;
            x++;
        }
        return ret;
    }
    public static long Comb2(long N, long R)
    {
        long Nume = 1;
        long Deno = 1;

        if (R > N - R) Swap(ref N, ref R);
        for (long i = 1; i <= R; ++i)
        {
            Deno *= i;
            Nume *= N - i + 1;
        }
        return Deno / Nume;
    }
    public static Dictionary<long, int> PrimeFactorization(long N)
    {
        var ret = new Dictionary<long, int>();
        for (long i = 2; i * i <= N; ++i)
        {
            int cnt = 0;
            while (N % i == 0)
            {
                cnt++;
                N /= i;
            }
            if (cnt != 0) ret[i] = cnt;
        }
        if (N >= 2) ret[N] = 1;
        return ret;
    }
    public static List<long> DivisorEnumrate(long N)
    {
        var ret = new List<long>();
        for (long i = 1; i * i <= N; ++i)
        {
            if (N % i == 0)
            {
                ret.Add(i);
                ret.Add(N / i);
            }
        }
        return ret;
    }
}
public class Factorical
{
    public long[] Fact;
    public long[] invFact;
    public Factorical(long N, long MOD = 1000000007)
    {
        Fact = new long[N + 1];
        invFact = new long[N + 1];
        Fact[0] = 1;

        for (long i = 1; i <= N; ++i)
        {
            Fact[i] = Fact[i - 1] * i % MOD;
        }
        invFact[N] = Pow(Fact[N], MOD - 2);

        for (long i = N; i > 0; --i)
        {
            invFact[i - 1] = invFact[i] * i % MOD;
        }

    }

    public long Comb(long n, long r, long MOD = 1000000007)
    {
        return (Fact[n] * invFact[r] % MOD * invFact[n - r] % MOD);
    }
}
public class BinarySearch
{
    public static int Lower_Bound<T>(T[] Array, T Target, Comparison<T> Comp)
    {
        var cmp = Comparer<T>.Create(Comp);
        var l = -1; //always ng
        var r = Array.Length; //always ok
        while (r - l > 1)
        {
            var mid = l + (r - l) / 2;
            var res = cmp.Compare(Array[mid], Target);
            if (res >= 0) r = mid;
            else l = mid;
        }
        return r;
    }
    public static int Upper_Bound<T>(T[] Array, T Target, Comparison<T> Comp)
    {
        var cmp = Comparer<T>.Create(Comp);
        var l = -1;
        var r = Array.Length;
        while (r - l > 1)
        {
            var mid = l + (r - l) / 2;
            var res = cmp.Compare(Array[mid], Target);
            if (res > 0) r = mid;
            else l = mid;
        }
        return r;
    }
}
public static class Utils
{
    public static void Swap<T>(ref T A, ref T B)
    {
        T x = A;
        A = B;
        B = x;
    }
    public static int DigitSum(int N)
    {
        string s = N.ToString();
        int ret = 0;
        for (int i = 0; i < s.Length; ++i) ret += s[i] - '0';
        return ret;
    }
    public static int[] Compress(long[] A)
    {
        var dic = new Dictionary<long, int>();
        long[] ar = new long[A.Length];
        A.CopyTo(ar, 0);
        Array.Sort(ar);
        int z = 0;
        foreach (var x in ar)
        {
            if (!dic.ContainsKey(x))
                dic[x] = z++;
        }
        return A.Select(c => dic[c]).ToArray();
    }
}
public class PriorityQueue<T> where T : IComparable<T>
{
    List<T> _item;
    public int Count { get { return _item.Count; } }
    bool _isascend { get; set; }
    public T Peek { get { return _item[0]; } }
    Comparison<T> Comp;
    public PriorityQueue(bool IsAscend = true) : this(Comparer<T>.Default.Compare, IsAscend) { }
    public PriorityQueue(Comparer<T> cmp, bool IsAscend, IEnumerable<T> list = null) : this(cmp.Compare, IsAscend, list) { }
    public PriorityQueue(Comparison<T> cmp, bool IsAscend = true, IEnumerable<T> list = null)
    {
        _item = new List<T>();
        this.Comp = cmp;
        if (list != null)
        {
            _item.AddRange(list);
            Build();
        }
    }

    private int Compare(int i, int j) => (_isascend ? 1 : -1) * _item[i].CompareTo(_item[j]);
    private void Swap(int i, int j) { var t = _item[i]; _item[i] = _item[j]; _item[j] = t; }
    private int Parent(int i)
        => (i - 1) >> 1;
    private int Left(int i)
        => (i << 1) + 1;
    public T Enqueue(T val)
    {
        int i = _item.Count;
        _item.Add(val);
        while (i > 0)
        {
            int p = Parent(i);
            if (Compare(i, p) > 0)
                Swap(i, p);
            i = p;
        }
        return val;
    }
    private void Heapify(int index)
    {
        for (int i = index, j; (j = Left(i)) < _item.Count; i = j)
        {
            if (j != _item.Count - 1 && Compare(j, j + 1) < 0) j++;
            if (Compare(i, j) < 0)
                Swap(i, j);
        }
    }
    public T Dequeue()
    {
        T val = _item[0];
        _item[0] = _item[_item.Count - 1];
        _item.RemoveAt(_item.Count - 1);
        Heapify(0);
        return val;
    }
    private void Build()
    {
        for (var i = (_item.Count >> 1) - 1; i >= 0; i--)
            Heapify(i);
    }
}
class Program
{
    static void Main(string[] args)
    {
        var ACCEPTED = new ACCEPTED();
        ACCEPTED.Solve();
    }
}
public static class io
{
    public static string Str => Console.ReadLine();
    public static string[] Strm => Str.Split(' ');
    public static long[] Longm => Strm.Select(long.Parse).ToArray();
    public static int[] Intm => Strm.Select(int.Parse).ToArray();
    public static char[] Charm => Str.ToArray();
    public static double[] Doublem => Strm.Select(double.Parse).ToArray();
    public static long Long1 => Longm[0];
    public static int Int1 => Intm[0];
    public static char Char1 => Charm[0];
    public static double Double1 => Doublem[0];
    public static long[] HorizontalRead(int N) { long[] A = new long[N]; for (int i = 0; i < N; ++i) A[i] = Long1; return A; }
    public static void Write(string a) => Console.WriteLine(a);
    public static void Write(params object[] i) => Write(string.Join(" ", i));
    public static void Write<T>(IEnumerable<T> a) => Write(string.Join(" ", a));
    public static void Horizontalwrite<T>(IEnumerable<T> a) { foreach (var z in a) Write(z); }
    public static void YN(bool i) { if (i) Write("Yes"); else Write("No"); }
}