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: Wrong Answer)

import java.util.*;
import java.io.*;

class Main {

	void solve () {

		char[] ar = in.next().toCharArray();
		Arrays.sort(ar);
		if (ar[0]==ar[1] && ar[2]==ar[3] && ar[1]!=ar[2]) out.println("Yes");
		else out.println("No");
		
	}

	public static PrintWriter out = new PrintWriter(System.out);
	public static Scanner in = new Scanner(System.in);
	public static void main(String[] args) {
		new Main().solve();
		out.flush();
	}

}