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 Go (1.6) (judge verdict: Accepted)

package main

import (
  "fmt"
  "os"
  "bufio"
)

func main() {
  sc := bufio.NewScanner(os.Stdin)

  sc.Scan()
  s := sc.Text()

  for i := 0; i < len(s) - 1; i++ {
    if s[i] == s[i + 1] {
      fmt.Println("Bad")
      os.Exit(0)
    }
  }

  fmt.Println("Good")

}