var str = readLine()!
for num in 0...3 {
  let a = str.index(str.startIndex, offsetBy: num)
  let b = str.index(str.startIndex, offsetBy: num+1)
  
   if str [a]==str [b] {
    print("Bad")
     break
   }
  else if num==3 {
    print("Good")
  }
}
  
