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 Atcoder_program_test_Csharp
{
    using System;
    class Program
    {
        static void Main(string[] args)
        {
            int S = int.Parse(Console.ReadLine());
            int A = S % 10;
            int B = S % 100 / 10;
            int C = S % 1000 / 100;
            int D = S / 1000;
            int count = 0;
            if (D == C)
            {
                Console.Write("Bad");
                count = count + 1;
            }
                if (C == B)
                {
                    if(count == 0)Console.Write("Bad");
                    count = count + 1;
                }
            if (B == A)
            {
                if (count == 0) Console.Write("Bad");
                count = count + 1;
            }
            if (count == 0) Console.Write("Good");
        }
    }
}