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 PHP (5.6.30) (judge verdict: Accepted)

<?php

//文字列の入力
fscanf(STDIN,"%4s",$s);


//数列を２つずつ分割
$a = substr($s,0,1);
$b = substr($s,1,1);
$c = substr($s,2,1);
$d = substr($s,3,1);

if ($a == $b || $b == $c || $c == $d){
    echo "Bad";
}else{
    echo "Good";
}