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;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ojtEx
{
    class Program
    {
        static void Main(string[] args)
        {
            //int X = int.Parse(Console.ReadLine());
            //int a = int.Parse(Console.ReadLine());
            string s = Console.ReadLine();

            //string[] xa = Console.ReadLine().Split(' ');
            //int x = int.Parse(xa[0]);
            //int a = int.Parse(xa[1]);


            //int ans = Solve(x, a);

            int x, y, z, w;
            x = int.Parse(s[0].ToString());
            y = int.Parse(s[1].ToString());
            z = int.Parse(s[2].ToString());
            w = int.Parse(s[3].ToString());


            string ans = S(x, y, z, w);

            Console.WriteLine(ans);
        }

        public static int Solve(int X, int A)
        {
            if (X < A)
            {
                return 0;
            }
            if (A <= X)
            {
                return 10;
            }

            return 0;
        }

        public static string S(int x, int y,int z,int w)
        {
            if(x!=y && y!=z && z!=w)
                {
                return "Good";
                }
            else
            {
                return "Bad";
            }
        }

    }
}