Problem:
Score : 100 points

Problem Statement

The door of Snuke's laboratory is locked with a security code.

The security code is a 4-digit number. We say the security code is hard to enter when it contains two consecutive digits that are the same.

You are given the current security code S. If S is hard to enter, print Bad; otherwise, print Good.

Constraints

S is a 4-character string consisting of digits.

Input

Input is given from Standard Input in the following format:

S

Output

If S is hard to enter, print Bad; otherwise, print Good.

Sample Input 1

3776

Sample Output 1

Bad

The second and third digits are the same, so 3776 is hard to enter.

Sample Input 2

8080

Sample Output 2

Good

There are no two consecutive digits that are the same, so 8080 is not hard to enter.

Sample Input 3

1333

Sample Output 3

Bad

Sample Input 4

0024

Sample Output 4

Bad

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;

class Program
{
    static string InputPattern = "InputX";

    static List<string> GetInputList()
    {
        var WillReturn = new List<string>();

        if (InputPattern == "Input1") {
            WillReturn.Add("3776");
            //Bad
        }
        else if (InputPattern == "Input2") {
            WillReturn.Add("8080");
            //Good
        }
        else if (InputPattern == "Input3") {
            WillReturn.Add("1333");
            //Bad
        }
        else if (InputPattern == "Input4") {
            WillReturn.Add("0024");
            //Bad
        }
        else {
            string wkStr;
            while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr);
        }
        return WillReturn;
    }

    static void Main()
    {
        List<string> InputList = GetInputList();
        string S = InputList[0];

        int UB = S.Length - 1;
        bool IsBad = false;
        for (int I = 0; I <= UB - 1; I++) {
            if (S[I] == S[I + 1]) {
                IsBad = true;
            }
        }
        Console.WriteLine(IsBad ? "Bad" : "Good");
    }
}