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;//list用
using System.Text;//StringBuilder用
using System.Collections;
using System.Linq;
class Program
{
    static List<int> s = new List<int>();
    static decimal result;
static Hashtable ht=new Hashtable();
static StringBuilder sb = new StringBuilder();
static int N,M,K;
static long[,] table;
    static void Main()
    {
        string tmp = Console.ReadLine();
      if(tmp[0]==tmp[1] || tmp[1]==tmp[2] || tmp[2]==tmp[3]){Console.WriteLine("Bad");}
      else{                    Console.WriteLine("Good");}
      return;
             //       Console.WriteLine(result.ToString());

    }


    static void Read1()//1項
    {
        string tmp = Console.ReadLine();
        N = int.Parse(tmp);
    }
 
    static void Read2()//複数項（項目数Ｎ）
    {
        string[] tmp = Console.ReadLine().Split(' ');
        for (int i = 0; i < N; i++) { s.Add(int.Parse(tmp[i])); }
    }
    static void Read3()//1行複数項
   {
       string[] tmp = Console.ReadLine().Split(' ');
       for (int i = 0; i < tmp.Length; i++) { s.Add(int.Parse(tmp[i])); }
    }
    static void Read4()//NK１行
    {
        string[] tmp = Console.ReadLine().Split(' ');
       N = int.Parse(tmp[0]);
       K = int.Parse(tmp[1]);
    }
    static void Read5()//N行K項
    {

 
    }


}