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;

namespace _20190622_ABC
{
    class Program
    {
        static void Main(string[] args)
        {
            var S = int.Parse(Console.ReadLine());
            int S1, S2, S3, S4;

            S1 = S / 1000;
            S2 = (S - S1 * 1000) / 100;
            S3 = (S - S1 * 1000 - S2 * 100) / 10;
            S4 = (S - S1 * 1000 - S2 * 100 - S3 * 10);
          
            if(S1 == S2 || S2 == S3 || S3 == S4) Console.WriteLine("Bad");
            else Console.WriteLine("Good");
        }
    }
}