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# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;

namespace newEx
{
    class Program
    {
        static void Main(string[] args)
        {
            //string[] l = Console.ReadLine().Split(' ');
            //int p = int.Parse(l[0]);
            //int q = int.Parse(l[1]);

            string l = Console.ReadLine();

            Console.WriteLine(S(l));
        }

        public static string S(string s)
        {
            char x, y, z, w;

            x = s[0];
            y = s[1];
            z = s[2];
            w = s[3];

            if (x != y && y != z && z != w)
            {
                return "Good";
            }
            else
            {
                return "Bad";
            }
        }
    }
}