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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

class Main {

    public static void main(String[] args) throws Exception {

        try {

            BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

            List<String> input = Arrays.asList(br.readLine().split(""));
            List<Integer> numbers = new ArrayList<>();

            for (String s : input) {
                numbers.add(Integer.parseInt(s));
            }
            
            String result = "Good";
            for (int i = 0; i < numbers.size() - 1; i++) {
                if (numbers.get(i) == numbers.get(i + 1)) {
                    result = "Bad";
                    break;
                }
            }

            System.out.println(result);
        } catch (IOException | NumberFormatException e) {
            e.printStackTrace();
            System.exit(0);
        } catch (final Exception e) {
            e.printStackTrace();
            System.exit(0);
        }
    }
}